            <<< EISNER::$2$DIA7:[NOTES$HIVOL]HARDWARE_HELP.NOTE;1 >>>
                               -< HARDWARE_HELP >-
================================================================================
Note 93.0         Low-end disk devices - The Digital difference      136 replies
EISNER::KENNEDY "Terry Kennedy"                      22 lines  16-JAN-1988 01:14
--------------------------------------------------------------------------------
The disk drives used in Digital's low-end systems are generally
slightly- or un-modified versions of devices available on the
open market. DEC's markup appears to average about 800% of the
best price you can get on the open market. For some, that is not
an unreasonable amount to pay for the security of an 'all-DEC'
system. For others (such as myself) it is entirely unnecessary.
There are several companies who will do you the 'favor' of sell-
ing you a DEC 'equal' drive for *only* a 400% mark-up.

Since the PC 'explosion', prices on these equivalent units are
very low due to the cut-throat pricing of the marketplace. I
therefore set out to determine what the differences (if any)
between the DEC device and the generic device are. This series
of notes will present my discoveries.

Please feel free to use this information in any way you choose,
but remember that neither I, Digital, nor the vendor you buy
the equipment from can be responsible for problems you may en-
counter. Having said that, let me also say that I will do my
best to help you overcome any problems, and that all of the
vendors I have used offered to give me a refund if the unit did
not work in my DEC system.
================================================================================
Note 93.1         Low-end disk devices - The Digital difference         1 of 136
EISNER::KENNEDY "Terry Kennedy"                      20 lines  16-JAN-1988 01:28
                                   -< RD52 >-
--------------------------------------------------------------------------------
The DEC RD52 comes in two flavors - the more common one is the
Quantum Q540 drive. The second-source drive, an Atasi AT3046,
was added due to shortages of the Q540 when DEC's demand was
highest. These drives will work on RQDX1, 2, or 3 controllers
at the current revision level. There are no differences between
the DEC and non-DEC flavors which prevent operation. DEC is
alleged to require tighter tolerances on drives made for them.

There is actually a third RD52 drive type. None of these units
were ever shipped to DEC customers, and the vendor ceased pro-
duction of disk drives. The manufacturer and model was the 
Evotek ET5540.

If you have one of these drives around, you can use it with
your DEC subsystem. Both drives are no longer manufactured in
any quantity, so I would advise against buying one. If you
must, however, they should be available in the $300-$400 range
from various surplus shops. I have used both models without
problems. Since this is the largest drive a RQDX1 will support,
you might want to investigate this option.
================================================================================
Note 93.2         Low-end disk devices - The Digital difference         2 of 136
EISNER::KENNEDY "Terry Kennedy"                      25 lines  16-JAN-1988 01:37
                                   -< RD53 >-
--------------------------------------------------------------------------------
The DEC RD53 is a Micropolis 1325 or 1335 drive with one mod-
ification. Earlier units were 1325s, current units are 1335s.
The modification is as follows [yes, it will probably void 
your warranty]: Turn the drive over so that the logic board
is facing you. Locate the two slotted screws and loosen them.
Lift the drive logic board up gently (it is hinged). Toward
the hinge end, locate the empty location marked R7. Solder a
jumper in. You now have a RD53. You will need to move the
drive select jumper to either 3 (for DU0 or expansion cabinet)
or 4 (for DU1).

One word of caution - if you are re-using your old drive's
skid plate (the slide mount bracket), be sure to tape over
the metal on the front end of the bracket or it will short
out the drive. DEC's RD53 skid plates have foam covering the
metal.

I have purchased three of these drives from Storage Dimen-
sions in California, (408) 395-2688. The cost was under
$850 each and they arrived in two days. They offer a one
year warranty on the drive, too. They call it a 'Model AT70',
but they're probably going to know what you mean if you
ask for 'the DEC drive' by now!

Of course, you need a RQDX2 or 3 to run this drive...
================================================================================
Note 93.3         Low-end disk devices - The Digital difference         3 of 136
EISNER::KENNEDY "Terry Kennedy"                      72 lines  16-JAN-1988 02:05
                                   -< RX33 >-
--------------------------------------------------------------------------------
The DEC RX33 is an IBM AT-type drive with some jumper changes.
DEC's drive is some variant of the TEAC FD55G. I have exper-
imented and discovered that the following drives/jumperings
work with the RQDX3:

TEAC FD-55GFV-17-U

Jumpers in:
HG
I (Roman numeral 1)
U1
U2
DC
FG
DS0 (for first RX33)
DS1 (for second RX33)

Jumpers out:
(all others)

Install the terminator, RA1, on the last (or only) drive

TEAC FD-55GFR-540-U

Jumpers in:
I (Roman numeral 1)
U0
U1
DC2
FG
D0 (for first RX33)
D1 (for second RX33)

Jumpers out:
(all others)

Install the terminator, RA1, on the last (or only) drive

Toshiba FDD 6882E1J01 (or ND-08DE-G)

Jumpers in:
LD
DC
DE
D1 (for first RX33)
D2 (for second RX33)

Jumpers out:
(all others)

Install the terminator jumper, TM, on the last (or only) drive

I have purchased many of the TEAC 540 drives from JDR Micro-
devices in California, (800) 538-5000. They have the follow-
ing items of interest:

FD-55G     High density drive - $129.95
FD-5Y      'Y' cable to power 2 drives from the BAnn box - $2.95
FD55-MHW   Mounting hardware for two FD-55G drives - $2.95
FD55-FP    Beige faceplate for FD-55G drive (black is std.) - $2.95
FD55-SPEC  Specification for FD-55G drive - $5.00
FD55-MAINT Maintenance manual for FD-55G drives - $25.00

Therfore, you can get two RX33's for $265.80 with the Y cable and
mounting hardware - a far cry from DEC's $795.00 each...

You need an RQDX3 to run these drives, of course. You will also
need to save the skid plate from your RX50 drive.

If you order these drives elsewhere, please remember that the
mounting hole threads are *metric*. Finding the right screws
will be a lot harder than finding the drives!
================================================================================
Note 93.4         Low-end disk devices - The Digital difference         4 of 136
EISNER::KOZAM                                        28 lines  17-JAN-1988 00:17
             -< Used DEC = Big Savings, No Compatability Problems >-
--------------------------------------------------------------------------------
	If you need all-DEC, but are comfortable with used equipment,
there are some bargains available.  For example, used DEC RD53s sell
for $ 700 each, including cables.  These are the real thing,
DEC labels and all.  New DEC RD53s, in the box, can be had for between
$ 1000 - $ 1200.  The EXACT same item through DECDirect lists for $ 3800.
Regardless of whether you got them used or new, field service will
take care of them (although at $ 700, it is probably cheaper to
replace, rather than repair them).

	Most used dealers are very reputable.  A 30 to 90 day warranty
is common and most places let you talk to their technical people if
you need help.  Some places don't do any testing - they just buy,
then ship to you.  Others are very thorough and clean up things up
so that it looks like new.  One caution, however, is to make sure
you get the small parts you need.  For instance, make sure you get
cables.  Often, all it takes is a reminder to the dealer that you
need them.

	A great source of used prices is a weekly publication called The
Processor, (800-247-4880).  I think you can get a free trial subscription
by calling.

	I've been very happy with my used equipment purchases and have
had fewer problems with used stuff than with new.

					Marc Kozam

Disclaimer - I'm not a dealer, just a happy player in the used market.
================================================================================
Note 93.5         Low-end disk devices - The Digital difference         5 of 136
EISNER::KENNEDY "Terry Kennedy"                       0 lines   4-FEB-1988 19:15
                  -< RD32 - see Note 92.3 in this conference >-
--------------------------------------------------------------------------------
================================================================================
Note 93.6         Low-end disk devices - The Digital difference         6 of 136
EISNER::KENNEDY "Terry Kennedy"                      12 lines   1-APR-1988 01:22
                                   -< RD54 >-
--------------------------------------------------------------------------------
The DEC RD54 is a Maxtor XT-2190. I have installed one of
these with no modifications in a Micro-11 system (with a
RQDX3 as the controller, of course).

I purchased the drive from Storage Dimensions in Califor-
nia, (408) 395-2688. The cost was under $1700 and it
arrived in two days. They offer a one year warranty on the
drive, too. They call it a 'Model AT133'.

Of course, you need an RQDX3 or the integrated thingie in
a MicroVAX 2000 to run this drive...

================================================================================
Note 93.7         Low-end disk devices - The Digital difference         7 of 136
EISNER::ETHINGTON "Superior Klingon Technology"       9 lines  14-MAY-1988 23:41
                         -< Wanted: Skid plate part # >-
--------------------------------------------------------------------------------
    Along these lines, folks.....does anyone know the part numbers for
    your friendly neighborhood field circus to sell you the plastic
    skid plate and big flat grounding spring/shield or whatever?  Lord
    knows you can get the same disk for enormously less loot than Storage
    Systems wants, but it would be nice to have the official skid plate
    hardware to hold it in place instead of rubber bands or string or
    whatever.....
    
    	Jerry
================================================================================
Note 93.8         Low-end disk devices - The Digital difference         8 of 136
EISNER::KILLEEN "Jeff Killeen"                        0 lines  15-MAY-1988 00:35
                   -< DEC WILL NOT SELL YOU THE SKID PLATE >-
--------------------------------------------------------------------------------
================================================================================
Note 93.9         Low-end disk devices - The Digital difference         9 of 136
EISNER::RICE "Gary Rice"                             12 lines  15-MAY-1988 09:12
--------------------------------------------------------------------------------
>< Note 93.8 by EISNER::KILLEEN "Jeff Killeen" >
>                   -< DEC WILL NOT SELL YOU THE SKID PLATE >-

Is this a new policy? I was able to buy 10 of the little puppies about
a year and a half ago thru DECdirect.

I don't remember the part number. It is packed away in my annual receipts
bag for 1986. However, if you need a small quantity, let me know via mail.
I could be convinced to part with 4 or 5 of them.


Gary
================================================================================
Note 93.10        Low-end disk devices - The Digital difference        10 of 136
EISNER::KOZAM                                         8 lines  15-MAY-1988 18:21
                    -< Skid Plate Part Number 74-25652-01 >-
--------------------------------------------------------------------------------
	The part number for skid plates (which I read off an RD53) is
74-25652-01 and is described as "112684 Skid" and is priced at only $ 5.00
each (that's a real surprise!).

	I don't know if that includes the metal grounding plate or just
the plastic part.

						Marc Kozam
================================================================================
Note 93.11        Low-end disk devices - The Digital difference        11 of 136
EISNER::KILLEEN "Jeff Killeen"                        3 lines  16-MAY-1988 18:26
                              -< HMMMMMM....... >-
--------------------------------------------------------------------------------
When I tried to buy one I was told by the E-store they were not
available for sale.  If you get them let us know - I will go out and buy
a dozen. 
================================================================================
Note 93.12        Low-end disk devices - The Digital difference        12 of 136
EISNER::RICE "Gary Rice"                             15 lines  18-MAY-1988 06:59
--------------------------------------------------------------------------------
>	The part number for skid plates (which I read off an RD53) is
> 74-25652-01 and is described as "112684 Skid" and is priced at only $ 5.00
> each (that's a real surprise!).

>	I don't know if that includes the metal grounding plate or just
> the plastic part.

74-25652-01 buys you the plastic "plate". Part number 74-28201-02 gets you
the metal "grounding strap". It is a bit more at $11.00 (1986 price). I
got BOTH from DECdirect by just calling and requesting these part numbers.
They were very helpful and gave no indication that I wasn't allowed to buy
these parts.


Gary
================================================================================
Note 93.13        Low-end disk devices - The Digital difference        13 of 136
EISNER::ETHINGTON "Superior Klingon Technology"       9 lines  29-MAY-1988 00:32
                                 -< Paydirt! >-
--------------------------------------------------------------------------------
    Thanks, folks!  I had the part number for the plastic skid plate,
    and had no difficulty at all ordering a batch - I think the price
    was still around $5.  I had never come up with the number for the
    big spring grounding plate doodad, though - I'll try ordering some
    of these critters now.
    
    DECUS to the rescue again, God help me I do love it so.....
    
    	Jerry
================================================================================
Note 93.14        Low-end disk devices - The Digital difference        14 of 136
EISNER::KENNEDY "Terry Kennedy"                       7 lines  29-MAY-1988 05:06
                          -< Logic of part numbers! >-
--------------------------------------------------------------------------------
>    ... still around $5.  I had never come up with the number for the
>    big spring grounding plate doodad, though - I'll try ordering some
>    of these critters now.
    
  The spring p/n should be a -02, where the plastic is -01.

	Terry
================================================================================
Note 93.15        Low-end disk devices - The Digital difference        15 of 136
EISNER::ETHINGTON "Superior Klingon Technology"      16 lines  21-JUN-1988 00:52
                          -< Stacking Hardware????? >-
--------------------------------------------------------------------------------
    Still further along these lines.....
    
    I understand that new mounting hardware is available to support
    stacking two half-height RD3x series Winchesters in a BA23 box.
    It is also apparently supported to stack a pair of RX33 half-height
    floppies, allowing you to stuff 2 Winchesters and 2 floppies in
    the BA23 box.  Assuming one has say an official DEC RD31 with skid
    plate and such, does anyone know what parts and cables need to be
    ordered to stack these varmints?  I've not seen the stacking setup;
    has anyone got one of these critters to see the cabling?  For instance,
    do you need a "Y" power cable to plug 2 Winchesters into one plug
    in the BA23 box?  How do the 2 floppies cable up?
    
    Inquiring minds want to know.....
    
    	Jerry
================================================================================
Note 93.16        Low-end disk devices - The Digital difference        16 of 136
EISNER::KENNEDY "Terry Kennedy"                      31 lines  21-JUN-1988 21:26
                        -< Possible, proceed carefully >-
--------------------------------------------------------------------------------
>    I understand that new mounting hardware is available to support
>    stacking two half-height RD3x series Winchesters in a BA23 box.

  My sales rep also 'understands' this - however, the only way we've
figured out to get the part numbers is to order an 11/53 and dissect
it. This is because the '53 is one of the only systems standard with
this 2-up stuff, and the 11/53 documentation is a few photocopied
addendum sheets which you may or may not get.

  You *will* need the BA23-UC (@$200.00) upgrade kit to properly put
2 winnies in the BA23. This kit gives you an extra set of ready/write
protect buttons, and deletes the two floppy WP indicators. [Yes, you
can do it without the -UC, but it isn't very pleasant and if you get
the drive selects wrong you will blow the format off *both* drives.]

>    It is also apparently supported to stack a pair of RX33 half-height
>    floppies, allowing you to stuff 2 Winchesters and 2 floppies in
>    the BA23 box.

  Yes, that is the maximum configuration. If you go for it, be *sure*
you have the current revision of the power harness or you'll go up in
smoke!. The current harness is individual wires with white plastic con-
nectors (between the power supply and the backplane).

  Anyway, to answer your question, I just went out and got the 'Y'
cable and the adapter plates from my local garage-based PC outfit. Most
places which will sell you RX33 look-alikes will gladly throw in the Y
and the plates with the order. I have ribbon-cable presses here, so I 
made my own data cables up. Again, your local PC place should be able
to make them up, once you convince them it's not a standard PC part and
that you know what you're doing...
================================================================================
Note 93.17        Low-end disk devices - The Digital difference        17 of 136
EISNER::KILLEEN "Jeff Killeen DECUServe Chair"       13 lines  21-JUN-1988 22:35
          -< AFTER MANY HRS OF WONDERING WHY I COULDN'T WRITE TO DU1 >-
--------------------------------------------------------------------------------
> [Yes, you
> can do it without the -UC, but it isn't very pleasant and if you get
> the drive selects wrong you will blow the format off *both* drives.]

Yes and No - Without the second set of buttons the second internal drive
comes up R/W on an RQDX1 and RO on a RXDX2 or RQDX3.  Trimarchi (no I don't
own stock in this company) sells the drives with the stacking hardware and
a special set of cables.  The cables de-activate the two front panel
disk buttons and forces the drives ready W/R all the time.

I found this one out the hard way......


================================================================================
Note 93.18        Low-end disk devices - The Digital difference        18 of 136
EISNER::MAYHEW "Bill Mayhew"                         15 lines  22-JUN-1988 10:36
               -< Drives w/stack hardware, and floating signals >-
--------------------------------------------------------------------------------
    There is a variant of both the RD31 and RD32 drives that "comes
    with" the stacking hardware, but that doesn't help a whole bunch
    if you already have the drive... for those that care, though, you
    should be able to find it readily (the words STK HDW or such are
    in the part title) on the Estore or in the USPL.
      I have reports from other folks who have put multiple Winchesters
    in a BA23 without the extra switches that what happens is the
    write-protect and drive-enable signal lines are left "floating".  
    Depending on the phase of the moon, your power supply (AC and DC), 
    etc., you can then have flaky problems where the drive suddenly
    drops off-line, or write-protects itself, without warning.  I don't
    know which controller was involved, though I think it was the RQDX1.
    The drives were RD52s, which are risky ANYWAY to double up in a
    BA23 because of power draw, but these folks did it...
     
================================================================================
Note 93.19        Low-end disk devices - The Digital difference        19 of 136
EISNER::KENNEDY "Terry Kennedy"                       7 lines  22-JUN-1988 20:50
                             -< Many variables... >-
--------------------------------------------------------------------------------
> Yes and No - Without the second set of buttons the second internal drive
> comes up R/W on an RQDX1 and RO on a RXDX2 or RQDX3.

  It depends on a number of things, including the revs of the RQDXn, whether
a RQDXE is also in the system, and the rev of the front panel. Also, you need
to jumper the first fixed disk as DS3 and the second as DS4, even if you have
the new front panel.
================================================================================
Note 93.20        Low-end disk devices - The Digital difference        20 of 136
EISNER::KENNEDY "Terry Kennedy"                      26 lines  27-JUN-1988 23:43
                          -< RX50 drive substitute! >-
--------------------------------------------------------------------------------
  Finally, a RX50 drive replacement!

  I have managed to convince a Toshiba IBM AT-type floppy drive that it
is an RX50. I've tested extensively with both XXDP+ and RSTS/E, but that
doesn't mean that it will work with other systems - you'll have to try
it and let me know.

  Here's what you need to do:

  1) Get a Toshiba ND-08DE-G drive kit from your local IBM garage oper-
     ation. (The actual drive is a Toshiba FDD6882E1J01)

  2) Set jumpers as follows: D1, TM, LD and DE on, all others off.

  3) Cut the trace leading to pin 2 on the data connector.

  4) Solder a wire from the drive side of the wire you cut in (3) to
     signal ground (the large solid areas on the circuit board)

  This has been tested on both the RQDX1 (M8639/M8639-YA) controller
with firmware 172E5/173E5, as well as with the RQDX2 (M8639-YB) with
firmware 188E5/189E5. With an RQDX3, you can use the same drive in
RX33 mode (see an earlier reply in this note).

  For the curious: what the above has done is forced the drive into
300 RPM/low density mode, and disabled the drive ready line.
================================================================================
Note 93.21        Low-end disk devices - The Digital difference        21 of 136
EISNER::HANRAHAN "Jamie Hanrahan, jeh@crash.cts.com" 10 lines  10-AUG-1989 19:57
                       -< Does RD53 change for uV2000? >-
--------------------------------------------------------------------------------
>< Note 93.2 by EISNER::KENNEDY "Terry Kennedy" >
>                                   -< RD53 >-
>
>The DEC RD53 is a Micropolis 1325 or 1335 drive with one mod-
>ification...

Is there anything different about the RD53 as used in the uV2000?
(We have a 2000 with a failing RD53...)

Also, can we drop an RD54 lookalike into instead?  
================================================================================
Note 93.22        Low-end disk devices - The Digital difference        22 of 136
EISNER::KOZAM                                         8 lines  10-AUG-1989 22:29
                       -< VS2000 RD53 is a regular RD53 >-
--------------------------------------------------------------------------------
> Is there anything different about the RD53 as used in the uV2000?
> (We have a 2000 with a failing RD53...)

	Nothing different from a regular RD53.

> Also, can we drop an RD54 lookalike into instead?  

	Don't know why not.  Never heard otherwise.
================================================================================
Note 93.23        Low-end disk devices - The Digital difference        23 of 136
EISNER::KENNEDY "Terry Kennedy"                       0 lines  10-AUG-1989 23:54
                       -< .-1 is correct on both counts >-
--------------------------------------------------------------------------------
================================================================================
Note 93.24        Low-end disk devices - The Digital difference        24 of 136
EISNER::HARVEY "Jack Harvey"                         12 lines  11-AUG-1989 04:44
                                -< Skid Plate >-
--------------------------------------------------------------------------------
       Trivial mechanical. The 2000 has mounting brackets that
       attach to holes in the sides of the raw 5.25" device.  You
       need to screw the black plastic (with floppy metal ground
       sheet) skid plate to the bottom of the raw device when
       mounting it in a BA23, 123, etc. 

       I have formatted lookalike RD54's on a 2000, loaded software
       and then moved the disk to a II.  No changes, other than
       screwing on a skid plate.
       
       If you are going the other direction, just remove the skid
       plate and save it for a friend. 
================================================================================
Note 93.25        Low-end disk devices - The Digital difference        25 of 136
EISNER::OSUDAR "John Osudar"                          6 lines  11-AUG-1989 13:32
                           -< Right -- no problems >-
--------------------------------------------------------------------------------
    Yup, the last several notes are right.
    
    We got two VS2000's diskless, bought an RD53-alike and an RD54-alike
    and put one in each, with no problem (other than the mounting change.)
    Subsequently got another RD54-alike, ripped out the 53 and put the
    54 in with no problems.  Beats paying DEC's prices... :-)
================================================================================
Note 93.26        Low-end disk devices - The Digital difference        26 of 136
EISNER::MCCORMICK_B "Virtual Bob"                     5 lines  12-AUG-1989 16:35
                            -< Disk format quirk? >-
--------------------------------------------------------------------------------
    Don't remember exactly (maybe someone else will remember...?!)
    but I believe there was a problem with some (maybe early) 2000's
    where if you formatted the disk on the 2000 it didn't result in
    the same amount of "formatted capacity" as when you formatted it
    on the RQDX3 ...
================================================================================
Note 93.27        Low-end disk devices - The Digital difference        27 of 136
EISNER::KOZAM                                        11 lines  14-AUG-1989 21:54
                       -< Never seen formatting trouble >-
--------------------------------------------------------------------------------
>  < Note 93.26 by EISNER::MCCORMICK_B "Virtual Bob" >
>                            -< Disk format quirk? >-

>    where if you formatted the disk on the 2000 it didn't result in
>    the same amount of "formatted capacity" as when you formatted it
>    on the RQDX3 ...

	While I can't conclusively state that this didn't ever occur, I've
never seen it.  Moving RD5X drives between 2000s and RQDX3s was pretty
common for me for a while and I never had trouble, even though several
versions of RQDX3 firmware were involved.
================================================================================
Note 93.28        Low-end disk devices - The Digital difference        28 of 136
EISNER::MCCORMICK_B "Virtual Bob"                    14 lines  20-AUG-1989 18:20
                    -< Maybe not problem - but different! >-
--------------------------------------------------------------------------------
| >  < Note 93.26 by EISNER::MCCORMICK_B "Virtual Bob" >
| >                            -< Disk format quirk? >-
|
| >    where if you formatted the disk on the 2000 it didn't result in
| >    the same amount of "formatted capacity" as when you formatted it
| >    on the RQDX3 ...
|
| 	While I can't conclusively state that this didn't ever occur, I've
| never seen it.  Moving RD5X drives between 2000s and RQDX3s was pretty
| common for me for a while and I never had trouble, even though several
| versions of RQDX3 firmware were involved.    

    I think you won't see it as a problem (or trouble) but if you did
    a SHOW DEV/FULL DUAn: you may see different "formatted" sizes!
================================================================================
Note 93.29        Low-end disk devices - The Digital difference        29 of 136
EISNER::KENNEDY "Terry Kennedy"                       8 lines  15-SEP-1989 22:41
                   -< Toshiba-as-RX50 doesn't work on RQDX3 >-
--------------------------------------------------------------------------------
>  I have managed to convince a Toshiba IBM AT-type floppy drive that it
> is an RX50. I've tested extensively with both XXDP+ and RSTS/E, but that
> doesn't mean that it will work with other systems - you'll have to try
> it and let me know.

  By the way, this *won't* work on an RQDX3 - it only works on the RQDX1
and RQDX2. Of course, you can use the Toshiba drive on the RQDX3 by setting
it up as an RX33 lookalike (see earlier note for jumper settings).
================================================================================
Note 93.30        Low-end disk devices - The Digital difference        30 of 136
EISNER::MCCORMICK_B "Bob McCormick"                   2 lines  19-SEP-1989 17:46
                            -< DEC stuff on PC's? >-
--------------------------------------------------------------------------------
    How about the (DEC) Teac FD-55GFV-57-U used on an XT or AT style
    machine?  Any ideas how to set up its jumpers, etc?
================================================================================
Note 93.31        Low-end disk devices - The Digital difference        31 of 136
EISNER::KENNEDY "Terry Kennedy"                       6 lines  20-SEP-1989 03:23
                                    -< Eh? >-
--------------------------------------------------------------------------------
>    How about the (DEC) Teac FD-55GFV-57-U used on an XT or AT style
>    machine?  Any ideas how to set up its jumpers, etc?

  I beg your pardon? You want to take a real DEC RX33 and use it on an
XT or AT? I'm not sure what you're trying to accomplish... If you could
clarify the "I have" and the "I want" parts, I'll give it a try...
================================================================================
Note 93.32        Low-end disk devices - The Digital difference        32 of 136
EISNER::HANRAHAN "Jamie Hanrahan, jeh@crash.cts.com" 12 lines   3-OCT-1989 19:38
                    -< Control panel for drives in BA123? >-
--------------------------------------------------------------------------------
So far our adventures in drive replacement have gone well.  Now I want
to ADD an RD53 lookalike to a uV2 (BA123).  

I have the drive, and am ordering the skid plate and ground strap.
Cables we can make.  

What about the control panel?  Is there a DEC part number for this
assembly?  (Presumably we need the panel and a cable to plug into
the "distribution board")

Can I use one of those PC-style Molex Y cables for power, or is there
a DEC part I should order?
================================================================================
Note 93.33        Low-end disk devices - The Digital difference        33 of 136
EISNER::HANRAHAN "Jamie Hanrahan, jeh@crash.cts.com"   1 line   3-OCT-1989 19:38
                          -< p.s. -- Thanks, folks! >-
--------------------------------------------------------------------------------
> So far our adventures in drive replacement have gone well.  
================================================================================
Note 93.34        Low-end disk devices - The Digital difference        34 of 136
EISNER::KOZAM                                        11 lines   3-OCT-1989 20:55
                          -< No need for front panel >-
--------------------------------------------------------------------------------
> What about the control panel?

	If the drive is going to be on-line and write-enabled at
all times, then you have no need for a panel.  I've never had any problem
with this arrangement.

> Can I use one of those PC-style Molex Y cables for power, or is there
> a DEC part I should order?

	You should have a power cable for each device slot in the BA123,
so a Y shouldn't be necessary.
================================================================================
Note 93.35        Low-end disk devices - The Digital difference        35 of 136
EISNER::KILLEEN "Jeff Killeen DECUServe Chair"       18 lines   5-OCT-1989 05:41
                          -< BA123 RD CONTROL PANELS >-
--------------------------------------------------------------------------------
> What about the control panel?  Is there a DEC part number for this
> assembly?  (Presumably we need the panel and a cable to plug into
> the "distribution board")

The RD control panel for a BA123 box is part # 54-16244-02

If there is a DEC RD drive in the BA123 you should already have the 
cable since it is a single cable for all four possible drives.  The 
cable's part # is 17-00862-01

Trimarchi sells a clone for $250 and it includes the cable if you ask 
for it.

> Can I use one of those PC-style Molex Y cables for power, or is there
> a DEC part I should order?

I don't understand this question.  All 5 1/4 inch mounting slots have a 
power cable available.  It is the standard PC type drive power cable.
================================================================================
Note 93.36        Low-end disk devices - The Digital difference        36 of 136
EISNER::HANRAHAN "Jamie Hanrahan, jeh@simpact.com"   32 lines  27-OCT-1989 17:24
                       -< Help needed formatting XT2190 >-
--------------------------------------------------------------------------------
In order to avoid "thread spread", I've copied the following query here.  
(Apologies to HARDWARE_HELP moderator for encroaching upon your turf!)
A possible answer follows in the next reply in THIS thread.  

            <<< EISNER::DUA0:[NOTES$LIBRARY]HARDWARE_HELP.NOTE;1 >>>
                               -< HARDWARE_HELP >-
================================================================================
Note 503.0                Help needed formatting XT2190                  1 reply
EISNER::SMITHJR "Charles T. Smith, Jr."              21 lines  27-OCT-1989 16:38
--------------------------------------------------------------------------------

I am having a problem formatting a Maxtor 2190 as an RD54.  The drive works
perfectly on the PC - it formats, will accept files, etc.

So far, we have tried a this on a couple different versions of the 
RQDX3, including C1, E3, and F4.  We've also used a couple different
sets of diags.  Using the F4 with the most recent version of diags, 
we an error indicating a DUP read command has timed out.  This occurs
after the drive has been formatting for roughly 11 minutes.  It does
the format, then apparently revectors bad sectors, and then seems to
go to sleep for a few minutes, after which the DUP error appears.

Earlier versions of software/controller would run for roughly 17 minutes
before encountering some kind of error.

I've also thought about trying to format the drive on a VAXstation 2000.
Does this controller produce a format compatable with the RQDX3?  If so,
can someone tell me what the various numbers the test71 formatter wants
when it does the format (xbnsiz, dnbsiz, etc).

Thanks.

================================================================================
Note 93.37        Low-end disk devices - The Digital difference        37 of 136
EISNER::HANRAHAN "Jamie Hanrahan, jeh@simpact.com"   20 lines  27-OCT-1989 17:26
                   -< Possible solution to XT2190 troubles >-
--------------------------------------------------------------------------------
Here is a note I grabbed off the Internet about a year ago:

> I had insidious problems with two XT-2190s, until it was determined my
> RQDX3 was bad.  
> 
> There is a problem formatting RD54s/XT2190s via DEC diagnostics on an
> RQDX3 with V3 firmware, if defects exist in particular cylinders over
> particular head ranges.  I have V2 firmware on my controller 
> (243E5/244E5 EPROMs), and both the format and the disk work fine.  
> 
> You do, however, have to ensure that the head write current is reduced
> for these drives, by tying the head select (HEADSEL 3) to REDUCWRTI.  
> This is done by jumpering W23 1-2.  If you don't do this, you can lose
> format on the drive.  A DEC field service notice also stated you have
> to jumper W23 3-4 for V2 and V3 (285E5/286E5 EPROMs) firmware. 
> 
> Brian Ruptash			Internet: bar@datapoint.com
> Principal Architect		uucp:	  uunet!dpmizar!bar
> Datapoint Corporation

================================================================================
Note 93.38        Low-end disk devices - The Digital difference        38 of 136
EISNER::KENNEDY "Terry Kennedy"                      10 lines  27-OCT-1989 22:54
                          -< Use non-default answers >-
--------------------------------------------------------------------------------
  I have formatted many XT2190's with RQDX3's "out of the box". I am not sure
of the accuracy of the information in the preceding note. Anyway, one of the
problems is that the formatter wants to read the disk before formatting it!
(well, actually it wants to read a part it *didn't* format after formatting
it).

  You need to take non-default answers to the questions about continuing
if the <mumble> is inacessible. Also, if you get asked if you want to download,
the answer is *yes*. Sorry to be so vague, but I haven't done one in a while
and my notes are at the office (and I'm not).
================================================================================
Note 93.39        Low-end disk devices - The Digital difference        39 of 136
EISNER::HARVEY "Jack Harvey"                         41 lines  28-OCT-1989 18:11
                       -< Formatting Disks on VS/MV2000 >-
--------------------------------------------------------------------------------
       Formatting on the MicroVAX 2000 or Vaxstation 2000 is
       a cinch, and it is the same format the RQDX3 wants.
       
       The following assumes you have the 2190 installed.
       If you need help with cracking open the *2000 box, there
       are a couple of excellent notes elsewhere, possibly
       this thread.  This example assumes the disk is in
       the CPU box, i.e, drive 0.  If it's in the expansion
       box, the alteration should be obvious. At the bootstrap:
       
       >>>TEST 70
       VSfmt_QUE_unitno (0-2) ? 0    <that's the drive selection
       
       Now you get some funny little progress reports (.....) just
       to let you know it's still alive. When formatting completes,
       the display is: 
       
       VSFfmt_STA_Siz ................. RD54
       
       The format execution time is 52 minutes.
       
       To verify the disk:
       
       >>>TEST 71
       VSmsv_QUE_unitno (0-1) ? 0   <again, your drive selection
       VSfmt_STS_Siz .................. RD54
       VSmsv_QUE_RUsure (DUA0 0/1) ? 1   <1 means yes, continue
       
       Verification takes 18 minutes.  At the end several
       other messages are displayed, such as bad blocks revectored,
       followed by:
       
       VSmsv_RES_Succ
       
       Execution Times, Minutes
       Disk    Format  Verify
       RD52	15	 4
       RD53	25	 7
       RD54	52	18
       
				       Have fun!
================================================================================
Note 93.40        Low-end disk devices - The Digital difference        40 of 136
EISNER::MAYHEW "Bill Mayhew"                         27 lines  30-OCT-1989 15:24
                 -< RQDX3 FCO re: formatting RD54s (XT2190s) >-
--------------------------------------------------------------------------------
< Note 93.37 by EISNER::HANRAHAN "Jamie Hanrahan, jeh@simpact.com" >
                   -< Possible solution to XT2190 troubles >-

>Here is a note I grabbed off the Internet about a year ago:
 
>> There is a problem formatting RD54s/XT2190s via DEC diagnostics on an
>> RQDX3 with V3 firmware, if defects exist in particular cylinders over
>> particular head ranges. ...
    
    In the Odd But True department, I just got a call from a client
    with a MicroPDP-11/73 who reported that DEC wanted to come and do
    some work on "her controller board" tomorrow...
    
    I called the DEC engineer and it sure sounds like they're fixing
    the same problem.  He said the problem is most insidious on MicroVAXes,
    but on either MicroVAXes or MicroPDPs (wasn't clear which), the
    formatter would, when formatting an RD54, just appear to hang after
    about 11 minutes.  There are a couple of other symptoms as well.
    
    I asked him for the FCO number, and he said: RQDX3-F002.  The EQ-kit
    (which contains 2 ROMs) is, he believes, EQ-01532-01.  (This probably
    could stand corroboration before anybody goes out and orders the
    thing.)  I have no other details at this time, but perhaps somebody
    with DEC-O-LOG (or whatever they call it now) can have a look and
    confirm...?
    

================================================================================
Note 93.41        Low-end disk devices - The Digital difference        41 of 136
EISNER::KENNEDY "Terry Kennedy"                      13 lines  30-OCT-1989 18:52
                   -< Yes, but it;s a new, hard-to-get FCO >-
--------------------------------------------------------------------------------
>    I asked him for the FCO number, and he said: RQDX3-F002.  The EQ-kit
>    (which contains 2 ROMs) is, he believes, EQ-01532-01.  (This probably
>    could stand corroboration before anybody goes out and orders the
>    thing.)

  Yes, this is that FCO. This FCO also fixes a number of other hangs and odd
events which were never officially admitted to by DEC (but if you cornered
the guy at Symposium you could get more info).

  This is one of the first FCO's under DEC's 'improved' FCO program - if you
are a self-maintenance customer, you have to DECmailer the whole board to get
the 2 lousy PROMS (cost $310.00). If this upsets you as much as it does me, I
suggest you see the Business_Practices conference for more info on the policy.
================================================================================
Note 93.42        Low-end disk devices - The Digital difference        42 of 136
EISNER::NORTON "Bill Norton"                          9 lines   2-NOV-1989 16:40
                           -< 4 RD53's on an RQDX3? >-
--------------------------------------------------------------------------------
    So how do I put 4 RD53's on an RQDX3 in a BA123 with 11/73 CPU?
    
    When I try to boot from DU3, it says "nonexistent drive".
    
    Moving the jumper plug on the signal distribution board to the upper
    pair of pins didn't seem to help.
    
    The pair of hardwired jumpers near the first one are starting to
    look awfully tempting to cut.
================================================================================
Note 93.43        Low-end disk devices - The Digital difference        43 of 136
EISNER::KOZAM                                         9 lines   2-NOV-1989 19:58
                            -< Unit select jumpers >-
--------------------------------------------------------------------------------
< Note 93.42 by EISNER::NORTON "Bill Norton" >
>    So how do I put 4 RD53's on an RQDX3 in a BA123 with 11/73 CPU?
    
	On a BA123 (unlike BA23, by the way), all drives should have
the unit select jumper (on the drives themselves) set to unit 3 (the
distribution board takes care of the unit selection).

	You shouldn't have to do anything with the controller or
distribution board.
================================================================================
Note 93.44        Low-end disk devices - The Digital difference        44 of 136
EISNER::SMITHJR "Charles T. Smith, Jr."              18 lines   9-NOV-1989 01:40
               -< Need more specifc stuff to format with VS2000 >-
--------------------------------------------------------------------------------
>       >>>TEST 70
>       VSfmt_QUE_unitno (0-2) ? 0    <that's the drive selection
>       
>       Now you get some funny little progress reports (.....) just
>       to let you know it's still alive. When formatting completes,
>       the display is: 
>       
>       VSFfmt_STA_Siz ................. RD54
>       

This is not what we get.... we get a message to the effect that the
controller cannot recognize the drive (which is quite possible, since
this drive has been used on a PC), and begins prompting for about 
20 cryptic parameters, some of which obviously relate to the number
of cylinders, etc...

Anyone know what numbers to feed these prompts?

================================================================================
Note 93.45        Low-end disk devices - The Digital difference        45 of 136
EISNER::MAYHEW "Bill Mayhew"                          7 lines   9-NOV-1989 10:33
                                -< Check DSIN? >-
--------------------------------------------------------------------------------
    I know there's an article on DSIN under the VS2000HW product
    (VAXstation 2000 Hardware) that covers formatting non-Digital disks,
    which is essentially what you have if you've formatted and used
    the disk on a PC.  I can't recall if there isn't also info there
    about what the magic numbers are for all those questions for normal
    DEC disks.  By rights, Colorado should be able to get 'em for you,
    though.
================================================================================
Note 93.46        Low-end disk devices - The Digital difference        46 of 136
EISNER::NORTON "Bill Norton"                          5 lines  13-NOV-1989 10:29
                         -< More RD53 info needed... >-
--------------------------------------------------------------------------------
    All 4 Rd53's are set to DS3.  Booting from #'s 0 & 1 works OK, as does
    #2 *if* #3 isn't installed.  If #3 is cabled, *it* gets active when 
    trying to boot #2, and then draws an error message.
    
    Aren't there some jumpers on the RQDX3 that can affect this?
================================================================================
Note 93.47        Low-end disk devices - The Digital difference        47 of 136
EISNER::KENNEDY "Terry Kennedy"                       9 lines  13-NOV-1989 23:39
                                -< Some ideas >-
--------------------------------------------------------------------------------
>    Aren't there some jumpers on the RQDX3 that can affect this?

Nope. W1 thru W11 are CSR, W12-W17 are unit number offset, W18-W22 were
deleted by product engineering, and W23 is for drives with more than 8
heads.

  Two possibilities: Do you have an RQDXE in the system? It can divert
drive selects in strange and wondrous ways. Also, is it possible you have
a bad RD53 which is responding to multiple selects?
================================================================================
Note 93.48        Low-end disk devices - The Digital difference        48 of 136
EISNER::KILLEEN "Jeff Killeen DECUServe Chair"       14 lines  14-NOV-1989 00:31
                            -< BA123 M9058 MODULE >-
--------------------------------------------------------------------------------
>                          -< More RD53 info needed... >-
> 
>     All 4 Rd53's are set to DS3.  Booting from #'s 0 & 1 works OK, as does
>     #2 *if* #3 isn't installed.  If #3 is cabled, *it* gets active when 
>     trying to boot #2, and then draws an error message.

On the BA123 signal board (M9058) are jumpers....

	W3, W4, W5, W6 all installed?

	and no RX drives installed

	and jumpers TP1, TP2, and TP3 removed?

================================================================================
Note 93.49        Low-end disk devices - The Digital difference        49 of 136
EISNER::NORTON "Bill Norton"                          4 lines  14-NOV-1989 13:51
                              -< Problem solved >-
--------------------------------------------------------------------------------
    Oops... never mind...
    
    Turns out the drive was last formatted on an RQDX2 controller. 
    After reformatting on the RQDX3 it works fine.
================================================================================
Note 93.50        Low-end disk devices - The Digital difference        50 of 136
EISNER::SMITHJR "Charles T. Smith, Jr."              30 lines  27-NOV-1989 00:47
                     -< Still having problems with X2190 >-
--------------------------------------------------------------------------------
The battle to format a Maxtor X2190 on an RQDX3 continues.  

Digital arrived and installed the latest revs to the RQDX3, and verified
all the jumpers, cables, etc, were installed/set to the correct values.
After this, we tried to format the drive.  After about 16 minutes, the
format died with a timeout on a DUP read function (whatever that is).

The funny thing is, this drive formats and runs perfectly on a PC.  We've
carried it back and forth a couple times to verify it's still working.

Digital brought in a real RD54, and it formatted without any problems.
We're using a late version of the diags (1989 version), have tried both
the Digital and customer formatters, and are flat out of ideas.  

Any suggestions?

The system is a microvax II with a BA123, 5 MB memory, ethernet, TK50,
and VCB01.  When we format, we usually stick the maxtor in as unit one,
booting off a RD53...though we have tried both floppy and tk50 to make
sure the disk based diags were not at fault.

An interesting note - before upgrading the RQDX3, we had 2 RD53's, an
RD52, and a pair of RX50's on the system (only one showed up).  When
we tried to boot this config on the new rev, the system would not boot...
could not see any disk.  Any ideas why this would happen?  Is there any
way to disable one of the RX50's in favour of a hard disk?  If not,
would installing an RQDX1 as a floppy controller make sense?  

Thanks.

================================================================================
Note 93.51        Low-end disk devices - The Digital difference        51 of 136
EISNER::KENNEDY "Terry Kennedy"                      91 lines  27-NOV-1989 19:51
                 -< Works here, all the gory details (long!) >-
--------------------------------------------------------------------------------
> Digital arrived and installed the latest revs to the RQDX3, and verified
> all the jumpers, cables, etc, were installed/set to the correct values.
> After this, we tried to format the drive.  After about 16 minutes, the
> format died with a timeout on a DUP read function (whatever that is).

> Digital brought in a real RD54, and it formatted without any problems.

  Ok, I took a 2190 new-in-the-box (never formatted by anything) and for-
matted it on an RQDX3. As I don't have a MicroVAX, I used the PDP-11 diag-
nostic ZRQCG0. The output is appeneded to the end of this note. The impor-
tant thing to remember is that DEC's default format mode is REFORMAT, which
assumes that the disk (or at least the FCT/RCT) is still readable. This is
not the case on a drive which has never "met" an RQDX3. Thus, you need to
specify the loading of the UIT and the bypassing of the RCT at the end of
the format pass, which sounds like the problem you have (the format pass is
10-15 minutes, after which it tries to read the defect list).

  I then took the drive, formatted it on a PC, and then re-formatted it on
the 2190. That worked as well, so the drive doesn't need to be brand new.
If you still can't get it to work, send me a Mail message and we can work
out you sending me your drive to be formatted (I have the Maxtor packaging
if you need it to send the drive).

DR> STA

CHANGE HW (L)  ? Y

# UNITS (D)  ? 1

UNIT 0
Enter controller IP address (O)  172150 ?
What unit do you want to format [0-255] (D)  0 ? 1
Would you like to revector a single LBN only [Y/N] (L) N ?
Do you want to use the "AUTOFORMAT" Mode [Y/N] (L) Y ? N


Would you like to use the RCT - Revector known bad blocks [Y/N] (L) N ?

**** WARNING ****

[text about don't proceed if you're just kidding deleted]

Do you wish to continue [Y/N] (L) Y ?


MSCP Controller Model:  19
    Microcode Version:   4

Do you want to use manufacturing bad block information [Y/N] (A) N ?

Downline load UIT [Y/N] (A) Y ?


 UIT  Drive Name
-------------------------------------------------------
  0   RD51
  1   RD52 part # 30-21721-02 (1 light on front panel)
  2   RD52 part # 30-23227-02 (2 lights on front panel)
  3   RD53
  4   RD31
  5   RD54
  6   RD32

Enter Unit Identifier Table (UIT) [0-7] (D)  ? 5

Continue if bad block information is inaccessible [Y/N] (A) N ? Y

Please type in the serial number [8-10 digits] (A)  ? 05388342


Formatting of Drive 1 Begin.

[a long sequences of messages is displayed here, 1 per minute, showing the
progress of formatting and what step is in progress on which block number.]

Format Completed.

00001 Rev LBNs
00000 Bad RBNs
00000 Bad DBNs
00000 Bad XBNs
00001 retired

FCT was not used.

Drive 1 has been formatted successfully.

ZRQC EOP    1
    0 TOTAL ERRS

DR> 
================================================================================
Note 93.52        Low-end disk devices - The Digital difference        52 of 136
EISNER::KENNEDY "Terry Kennedy"                      30 lines  27-NOV-1989 20:03
                      -< Thoughts on the 5-unit problem >-
--------------------------------------------------------------------------------
> An interesting note - before upgrading the RQDX3, we had 2 RD53's, an
> RD52, and a pair of RX50's on the system (only one showed up).  When
> we tried to boot this config on the new rev, the system would not boot...
> could not see any disk.  Any ideas why this would happen?  Is there any
> way to disable one of the RX50's in favour of a hard disk?  If not,
> would installing an RQDX1 as a floppy controller make sense?  

  Well, it always was an illegal configuration 8-).

  Seriously, there are 4 drive selects available, therefore a maximum of
4 units possible per RQDXn. The X1 limits this to 2HD+floppy, whereas the
X2 and X3 can have up to 4 hard disk units. In your example, *something*
was conflicting. Being a dual board (1/2 the size of the RQDX1/2), the X3
may have some "economizing" of the select logic which is causing the prob-
lem.

  I would junk the RX50 and install an RX33 clone (see seperate replies here
for more info). This will give you 3x the capacity of the RX50, as well as
the ability to read RX33 media (sometimes a big savings over tapes). I think
using an RQDX1/2 as a floppy-only controller is a bad idea, because:

  1) It's a power pig. Given the power supply in the BA23, this can be a major
issue.

  2) It takes up a quad slot for no (good) purpose.

  3) Many bootstraps have problems finding non-primary MSCP disks (only a
problem if you plan to boot RX50, I admit).

  I hope this helps. Leave a reply if you need more information.
================================================================================
Note 93.53        Low-end disk devices - The Digital difference        53 of 136
EISNER::SMITHJR "Charles T. Smith, Jr."              22 lines  27-NOV-1989 23:16
                              -< More 2190 stuff >-
--------------------------------------------------------------------------------
>  Ok, I took a 2190 new-in-the-box (never formatted by anything) and for-
>matted it on an RQDX3. As I don't have a MicroVAX, I used the PDP-11 diag-
>nostic ZRQCG0. The output is appeneded to the end of this note. The impor-
>tant thing to remember is that DEC's default format mode is REFORMAT, which
>assumes that the disk (or at least the FCT/RCT) is still readable. This is
>not the case on a drive which has never "met" an RQDX3. Thus, you need to
>specify the loading of the UIT and the bypassing of the RCT at the end of
>the format pass, which sounds like the problem you have (the format pass is
>10-15 minutes, after which it tries to read the defect list).

The vax diags prompt for loading bad blocks, etc, and allow you to load the
UIT.  We did all this, albeit on a Vax.

>  I then took the drive, formatted it on a PC, and then re-formatted it on
>the 2190. That worked as well, so the drive doesn't need to be brand new.
>If you still can't get it to work, send me a Mail message and we can work
>out you sending me your drive to be formatted (I have the Maxtor packaging
>if you need it to send the drive).

I've got a couple other things I'm going to try.  If they turn up dry, I 
might take you up on your kind offer.  Thanks!

================================================================================
Note 93.55        Low-end disk devices - The Digital difference        55 of 136
EISNER::HUDGINS "Jerry Hudgins"                       9 lines   4-JAN-1990 09:40
                        -< Sorry, you need another box >-
--------------------------------------------------------------------------------
>> We just got a VAXstation 2000 that has an RD54 plus the expansion box with
>> a TK50.  We have a second RD54 that we want to put in the expansion box.

    Unless you're a very clever cabler indeed, you won't be putting
    the second RD54 in the TK50 expansion box.  You need a SECOND
    expansion box for the drive, which uses a different cable (it
    doesn't daisy-chain from the TK50 box).  I believe this box is
    a BA40B; I've never seen it sold without a drive already installed
    (as a RD54-FA, for example).
================================================================================
Note 93.56        Low-end disk devices - The Digital difference        56 of 136
EISNER::DAVIS "Steven P. Davis"                       2 lines   4-JAN-1990 12:16
--------------------------------------------------------------------------------
    I would not consider the question a kindergarten level
    question.
================================================================================
Note 93.58        Low-end disk devices - The Digital difference        58 of 136
EISNER::DOW "Bruce Dow, STS Consultants"             11 lines   7-JAN-1991 14:33
                          -< Better late than never >-
--------------------------------------------------------------------------------
> It looks like we'll be getting a second cabinet for the other drive, and the
> cables will no doubt be included.
    
    Well, we're finally getting the second cabinet and RD54 (and a 12 Meg
    daughterboard).
    
    Q:  What cable do I need to make sure comes with the RD54?
    
    The expansion adapter currently only has an A connector (for the TK50).
    How do I get a B connector added for the second RD54?
    
================================================================================
Note 93.59        Low-end disk devices - The Digital difference        59 of 136
EISNER::DOW "Bruce Dow, STS Consultants"             36 lines  15-JAN-1991 13:00
             -< Where do the expansion adapter ribbons come from? >-
--------------------------------------------------------------------------------
Marc Kozam asked me for more information about my configuration.

I have a VAXstation 2000 (VS450-EA) with 6MB, B/W, 19" monitor           
with TK50Z-FA (TK50,CTRL, EXP BOX) with a BA40A-AA Expansion Adapter     
attached to the bottom of the VS2000 system box.  I have a RD54          
hard drive (FS-MXTO2-AA) inside the system box.                          
                                                                         
This initial setup (VS2000, TK50, and RD54) works fine.  I'm planning    
to order a RD54 & expansion box and 12MB of memory, trading in the       
4MB daughterboard and an RD53 drive.  I have a quote for $2400 from      
Compurex.  The RD53 was never in this system.                            
                                                                         
I once had the VS2000 system box apart to look at the memory.  It was    
then that I noticed that only the connector A in the Expansion Adapter   
was there.  The connector B is not brought down to the Expansion         
Adapter.  Is the connector B inside the system box, or does it need      
to be ordered.                                                           
                                                                         
The tape drive cable is BC19.  The disk drive cable I need is BC17Y.     
                                                                         
The main issue for me is where does the B connector within the           
expansion adapter come from.                                             
                                                                         
I'm not opposed to a 3rd party expansion box, but this system does       
need to be contained--it sits on a desk in our spare bedroom, and        
my 21 month old daughter does have access to it--she loves to            
play on the keyboard.                                                    


	Maybe another way to think about the problem is to ask
where do the cables/ribbons come from that connect the VAXstation
2000 system box to the expansion adapter connectors A & B?

Do they come with the VS2000 system or with the expansion
adapter?  What are their part numbers?

================================================================================
Note 93.60        Low-end disk devices - The Digital difference        60 of 136
EISNER::DOW "Bruce Dow, STS Consultants"             23 lines  23-JAN-1991 14:24
                    -< Ribbons come with expansion adapter >-
--------------------------------------------------------------------------------
> Do they (expansion adapter ribbons) come with the VS2000 system or with 
> the expansion adapter?  What are their part numbers?
    
From:	EISNER::KOZAM        16-JAN-1991 18:14:58.46
To:	EISNER::DOW
CC:	
Subj:	RE: VS expansion adapter ribbons


	Sorry it's taking so long to sort this out - unfortunately, I'm
not where I usually work, so I don't have access to my favorite VAXstation
documents.  To your latest question about cables between the VAXstation
2000 system box and the expansion adapter - yes, all cables are shipped with
the expansion adapter, the VAXstation itself comes with NO cables.

	Of course, you still need the cable between the RD5X expansion box
and the expansion adapter.  It IS possible that someone didn't bother to
install all of the expansion adapter ribbons - I'm pretty certain that the
disk ribbons (2 of them) are entirely separate from the tape ribbon (1 of them).
	Does that answer your question, or do you now need part numbers?

Marc
    
================================================================================
Note 93.61        Low-end disk devices - The Digital difference        61 of 136
EISNER::DOW "Bruce Dow, STS Consultants"             30 lines  23-JAN-1991 14:25
                      -< Should be three adapter ribbons >-
--------------------------------------------------------------------------------
From:	EISNER::KOZAM        17-JAN-1991 18:40:21.75
To:	EISNER::DOW
CC:	
Subj:	RE: VS expansion adapter ribbons


	The adapter ribbons SHOULD be keyed, so I don't think you can mess
up.  If I recall correctly, there are three connectors involved - a 50
pin connector that handles all tape drive functions, a 60 pin connector
that handles disk drive selection, head selection, and seeking for
both drives plus data transferred to/from drive 0, and a 20 pin
connector that handles data transferred to/from drive 1.

	There is NO DEC supported way to configure 2 RDXX drives plus an
RX33, although this IS possible - I use this configuration all the time.
(Haven't tried it with a tape drive as well, but I don't expect any problem
here.)

	Since I see you are doing this for home consumption, I assume
that you are somewhat cost sensitive.  My costs for adding an RD53
totalled about $ 50 for cabling + drive cost.  Add $ 100 for a nice
enclosure - important with children/pets around, as in your case.
Of course, I understand that for some people, a supported setup is
worth the extra cost - especially for those without the time or the
experience to start making cables.  If you want to take a chance, though,
the cost savings can be substantial.

	Good luck - please post anything you learn.

Marc
================================================================================
Note 93.62        Low-end disk devices - The Digital difference        62 of 136
EISNER::DOW "Bruce Dow, STS Consultants"             32 lines  23-JAN-1991 14:26
                         -< Missing drive one ribbon >-
--------------------------------------------------------------------------------
> 	The adapter ribbons SHOULD be keyed, so I don't think you can mess
> up.  If I recall correctly, there are three connectors involved - a 50
> pin connector that handles all tape drive functions, a 60 pin connector
> that handles disk drive selection, head selection, and seeking for
> both drives plus data transferred to/from drive 0, and a 20 pin
> connector that handles data transferred to/from drive 1.

	I opened up my VS2000 box and found the 50 pin connector ribbon 
that handles the tape drive (P/N 17-01244-01, which attaches to the 
motherboard and to the A Connector in the expansion adapter).  All 
connectors on the motherboard are male.  I found the 60 pin connector
multi-color ribbon (no part number I could read) that connects to the
motherboard and part of the other end of this ribbon connects to 
drive 0.  An unused part of this ribbon has a 34 pin female connector
and is not currently connected to anything.  It is not long enough to
reach the expansion adapter.

Q:	What, if anything, should this 34 pin connector connect to?

I also found a 20 pin male connector on the motherboard, but have no
ribbon for it.  

Q:	Is this the one that is supposed to handle data transfer
	to/from drive 1?

Q:	What is the part number for this missing ribbon? 

	or what are the cabling pinouts and what ends (P/N?) do I need 
	in order to connect to the BC17Y disk drive cable that is supposed 
	to connect to Connector B in the expansion adapter?  (I've made 
	my own RS-232 cables before.)

================================================================================
Note 93.63        Low-end disk devices - The Digital difference        63 of 136
EISNER::DOW "Bruce Dow, STS Consultants"             17 lines  19-APR-1991 19:15
                  -< Which RD53 drive select jumper to move? >-
--------------------------------------------------------------------------------
>	<<< Note 93.2 by EISNER::KENNEDY "Terry Kennedy" >>>
>				-< RD53 >-
    
> You now have a RD53. You will need to move the
> drive select jumper to either 3 (for DU0 or expansion cabinet)
> or 4 (for DU1).
    
    The RD53 I have is a DEC RD53, Micropolis drive 1325D, with
    R7 already soldered in.
    
    I have blue jumpers on W1, W2, W8, and DS2.  Do I need to
    move the jumper on DS2 to DS4 for an external DUA1 drive?
    
    Or do I need another jumper?  If so, where can I get one?
    
    Thanks.
    
================================================================================
Note 93.64        Low-end disk devices - The Digital difference        64 of 136
EISNER::KENNEDY "Terry Kennedy"                      16 lines  20-APR-1991 05:16
                             -< More info needed >-
--------------------------------------------------------------------------------
>    I have blue jumpers on W1, W2, W8, and DS2.  Do I need to
>    move the jumper on DS2 to DS4 for an external DUA1 drive?

  The DSn jumper sets the physical unit number for the drive. Combined
with the LUN offset (set on the controller) that determines the unit
number reported to the operating system.

  Normally the 3rd (of 4) drive select is used, no matter what the box.
an RQDXE expander card handles the translation for you. Infinite other
combinations are possible, so I'll need to know what's in the box, what
expander you're using, and what external box you have to give a better
explanation.

  Note: If you have 2 drives that the controller thinks are at the same
drive select (even if they aren't) you may lose the format on either or
both of them, _even if you have the write protect switch on_.
================================================================================
Note 93.65        Low-end disk devices - The Digital difference        65 of 136
EISNER::DOW "Bruce Dow, STS Consultants"              8 lines  20-APR-1991 11:26
--------------------------------------------------------------------------------
    I'm using Marc Kozam's home-brew cabling scheme to add a second
    external disk drive (RD53) to a VS2000.  DUA0 (RD54) is an internal
    drive.  I have a RQDX3 controller.
    
    Marc responded by mail that I need to move the jumper on DS2 to
    DS4.
    
    Thanks for your help.
================================================================================
Note 93.66        Low-end disk devices - The Digital difference        66 of 136
EISNER::KENNEDY "Terry Kennedy"                       3 lines  21-APR-1991 03:12
                              -< General layout >-
--------------------------------------------------------------------------------
  Yes. In the absence of any external "steering" logic, the first hard
disk is unit 3 (of 4) and the second is 4 (of 4). A floppy, if present,
goes on unit 1 (and if it's an RX50 it uses unit 2 as well).
================================================================================
Note 93.67        Low-end disk devices - The Digital difference        67 of 136
EISNER::CAMPBELL "Milton Campbell"                   11 lines  17-MAY-1991 21:47
                     -< Combination RD53/RD54 with RQDX3 >-
--------------------------------------------------------------------------------
    I am trying to add an (external) RD54 (Maxtor) equivalent to a BA23 
    (VAX) with an existing RD53 and an RQDX3.  The flyer I got with the
    Maxtor says to install both jumper at location W23.  When I do this,
    the RD53 no longer boots.  The RD53 ROM numbers are 244E5 and 243E5. 
    The Maxtor supplier says I need later ones (340E5 and 339E5) and is 
    shipping me a set.  Does this make sense?
    
    What else might I have to do to have a mixed (RD53/RD54) system?
    
    Milt.
    
================================================================================
Note 93.68        Low-end disk devices - The Digital difference        68 of 136
EISNER::KENNEDY "Terry Kennedy"                      26 lines  19-MAY-1991 03:59
                   -< Probably 2 drives on the same select >-
--------------------------------------------------------------------------------
>    I am trying to add an (external) RD54 (Maxtor) equivalent to a BA23 
>    (VAX) with an existing RD53 and an RQDX3.  The flyer I got with the
>    Maxtor says to install both jumper at location W23.  When I do this,
>    the RD53 no longer boots.  The RD53 ROM numbers are 244E5 and 243E5. 
>    The Maxtor supplier says I need later ones (340E5 and 339E5) and is 
>    shipping me a set.  Does this make sense?
    
  Note that this configuration is only supported with the external RD
in an RD5X-DA box via an RQDXE.

  However, having said that 8-)

1) 339/340 are needed for reliable RD54 operation in any configuration.
   The W23's are to enable the additional head select.

2) I suspect you have both drives at the same drive select. There are
   some jumpers on the Maxtor, usually like this:

   1 C 2  3 C 4

  I suspect you have a jumper between 3 and C. You'll need to move it to
C and 4.

  NOTE: If the above is the problem, you may need to reformat the RD53
and/or the Maxtor. You'll know if you have to - one or both may be un-
readable.
================================================================================
Note 93.69        Low-end disk devices - The Digital difference        69 of 136
EISNER::CAMPBELL "Milton Campbell"                    9 lines  20-MAY-1991 09:31
                   -< Doesn't Work - Even With Only 1 Drive >-
--------------------------------------------------------------------------------
> 2) I suspect you have both drives at the same drive select. There are
>    some jumpers on the Maxtor, usually like this:
    
    I don't think this is it.  With the W23 jumpers in, I can't boot the
    RD53 even when the Maxtor is NOT CONNECTED.  Removing the W23 jumpers
    makes things work.  The symptom is that the boot sequence hangs in the
    "2.." stage.
    
    Milt.
================================================================================
Note 93.70        Low-end disk devices - The Digital difference        70 of 136
EISNER::KENNEDY "Terry Kennedy"                       5 lines  20-MAY-1991 16:33
                    -< Try this for a better error message >-
--------------------------------------------------------------------------------
>    makes things work.  The symptom is that the boot sequence hangs in the
>    "2.." stage.
    
  That means the drive isn't being seen and the "sniffer" boot is looking
for other units. What do you get if you try an explicit boot like B DUA0?
================================================================================
Note 93.71        Low-end disk devices - The Digital difference        71 of 136
EISNER::CAMPBELL "Milton Campbell"                   18 lines  20-MAY-1991 21:07
                  -< Device offline - time to replace RQDX3 >-
--------------------------------------------------------------------------------
>  That means the drive isn't being seen and the "sniffer" boot is looking
>for other units. What do you get if you try an explicit boot like B DUA0?
    
    B DUA0
    
    yields
    
    2..
    ?4D DEVOFFLINE, DUA0
    ?06 HLT INST
         PC = 00000EE6
    Failure
    
    So you appear to be right.  I get the same thing if I put in upgraded
    PROMs.  My guess is that it is the RQDX3 (although it still works fine
    if I take off the W23 jumpers).
    
    Milt.
================================================================================
Note 93.72        Low-end disk devices - The Digital difference        72 of 136
EISNER::KENNEDY "Terry Kennedy"                       8 lines  20-MAY-1991 22:42
                  -< Do you have the right jumper position? >-
--------------------------------------------------------------------------------
>    So you appear to be right.  I get the same thing if I put in upgraded
>    PROMs.  My guess is that it is the RQDX3 (although it still works fine
>    if I take off the W23 jumpers).
    
  Are you sure you've found W23? Should be 4 pins in a vertical line near
the top left of the board, as I recall (subject to memory parity errors 8-).
If you've jumpered any of the other jumpers (CSR, LUN offset) you could get
the result you're seeing...
================================================================================
Note 93.73        Low-end disk devices - The Digital difference        73 of 136
EISNER::BURNS "Scott Burns"                           3 lines  21-MAY-1991 14:51
                                  -< Powerup >-
--------------------------------------------------------------------------------
Are you running both RD5x drives in the main BA23 box ? Watch out for your
powersupply when the drives startup. Startup on these full size drives draws a
lot of juice.
================================================================================
Note 93.74        Low-end disk devices - The Digital difference        74 of 136
EISNER::CAMPBELL "Milton Campbell"                   11 lines  21-MAY-1991 21:32
               -< Thank you - DECUServe proves its worth again >-
--------------------------------------------------------------------------------
>   Are you sure you've found W23? Should be 4 pins in a vertical line near
> the top left of the board, as I recall (subject to memory parity errors 8-).
> If you've jumpered any of the other jumpers (CSR, LUN offset) you could get
> the result you're seeing...
    
    That's it.  I blindly failed to notice that the jumpers were already
    installed and just jumpered the two closest open ones (W12 and W13).
    
    Thanks a lot.
    
    Milt.
================================================================================
Note 93.75        Low-end disk devices - The Digital difference        75 of 136
EISNER::CAMPBELL "Milton Campbell"                    7 lines  21-MAY-1991 21:35
                           -< 2nd drive is external >-
--------------------------------------------------------------------------------
> Are you running both RD5x drives in the main BA23 box ? Watch out for your
> powersupply when the drives startup. Startup on these full size drives draws a
> lot of juice.
    
    So far, I am not even trying to run the second drive.  It will be in an
    external box.  Initially the RD53 will be internal and the RD54
    external, but once things work, I'll probably switch them around.
================================================================================
Note 93.76        Low-end disk devices - The Digital difference        76 of 136
EISNER::KENNEDY "Terry Kennedy"                        1 line  22-MAY-1991 02:32
                            -< Glad I could help! >-
--------------------------------------------------------------------------------
               -< Thank you - DECUServe proves its worth again >-
================================================================================
Note 93.77        Low-end disk devices - The Digital difference        77 of 136
EISNER::KENNEDY "Terry Kennedy"                      15 lines  19-JUL-1991 01:40
                   -< Newer Teac model for RX33 substitute >-
--------------------------------------------------------------------------------
  A number of people have asked me for other RX33 substitutes, since the
Teac models I gave earlier in this thread are no longer available. I did
some experimenting and I have a new one for you:

  The Teac FD-55GFR-149-U can be used as an RX33 by installing jumpers
on FG, DC, I, and D0 (for 1st drive) or D1 (for 2nd drive). The "I" jum-
per is hard to find - here's a picture:

  LG o o
  IS o o o<---- This is the "I" jumper
         o<-/
DC o o o o 
     o o o 

  I've tested this with RX50 and RX33 media under XXDP+ and RSTS/E.
================================================================================
Note 93.78        Low-end disk devices - The Digital difference        78 of 136
EISNER::DOW "Bruce Dow, STS Consultants"             49 lines  26-SEP-1991 10:44
                         -< More RD54 RQDX3 questions >-
--------------------------------------------------------------------------------
    We have a RD54 Maxtor XT-2190 drive.  The manual addendum from
    Midwest Systems Technical Support says:

    		READ BEFORE INSTALLING DISK DRIVE	2/89

    			RD54 MAXTOR

    * WARNING: This disk drive has been hardware formatted for an 
    RQDX3.  Do not attempt to format this drive on a MicroVAX using
    the Customer Confidence Diagnostics.  The format is not compatible
    with this drive.  If reformat is absolutely necessary, please
    contact Midwest Systems Technical Support Department first.

    1.	The RQDX3 being used MUST be inspected to determine its
    	version, and the W23 jumper MUST be configured accordingly:
    	(FAILURE TO DO SO MAY DESTROY THE HARDWARE FORMAT.)

    	Version 3 Identification

    	IF:	Location 1: ROM 244E5, or 286E5;
    		Location 2: ROM 243E5, or 285E5
    	THEN:	at W23 jumper between post 1 & 2 only.

    	Version 4 Identification

    	IF:	Location 1: ROM 340E5;
    		Location 2: ROM 339E5
    	THEN:	at W23 jumper between posts 1 & 2, and 3 & 4.

    2.	Depending on the drive version, set the white or blue unit
    	select jumper (located in the rear of the drive on the printed
    	circuit board) between C and 3 or 2 and 3 for drive zero (0).

    -------------
    I want to install this on a VS2000 as drive DUA1.  I will be
    replacing an external RD53 (attached via Marc Kozam's home brew
    cabling scheme described in another topic), which was successfully
    formatted with this controller. 

    Is there any way to tell the RQDX3 version without physically 
    examining the drive controller board?

    The XT-1000/2000 Family Disk Drives Quick Reference guide says to
    jumper between 1 & C for drive zero or between 2 & C for drive one.
    The RD54 was previously in a MVII as DUA2 with a jumper between 3 & C.
    (The Micro Systems addendum seems to conflict; which is correct?)

    Do I need to reformat the disk?  Is it even safe to do so?

================================================================================
Note 93.79        Low-end disk devices - The Digital difference        79 of 136
EISNER::DOW "Bruce Dow, STS Consultants"             21 lines  26-SEP-1991 10:47
                        -< RD54 Spindle motor control >-
--------------------------------------------------------------------------------
    The XT-1000/2000 Quick Reference Guide describes the Spindle Motor
    Control:

    	With Jumper JE installed, the spindle motor can then be
    controlled via J2-5 on the interface [20 pin] connectectors.
    A low level on this pin will keep the spindle from powering up
    with system power is applied.  This feature is used to allow
    proper sequencing on multi-drive systems.  With jumper JE
    not installed, the spindle motor will start upon applying
    voltage to the drive.

    ----------
    The RD54 to be installed already has JE jumpered.  Both the
    internal RD54 and this new RD54 will be drawing power off the
    system box (VS2000).  

    Will this JE jumper prevent both drives drawing the huge power
    surge on startup?  If so, what starts the second drive?  Does
    the RQDX3 controller automatically handle this, or does some
    command need to be inserted in the startup procedure?

================================================================================
Note 93.80        Low-end disk devices - The Digital difference        80 of 136
EISNER::KENNEDY "Terry Kennedy"                      45 lines  26-SEP-1991 15:59
                           -< More detailed advice >-
--------------------------------------------------------------------------------
>    We have a RD54 Maxtor XT-2190 drive.  The manual addendum from
>    Midwest Systems Technical Support says:

  Hopefully you didn't pay them a lot for the drive. [On general principles.
New XT-2190's can be had for about $8-900].

>    1.	The RQDX3 being used MUST be inspected to determine its
>    	version, and the W23 jumper MUST be configured accordingly:
>    	(FAILURE TO DO SO MAY DESTROY THE HARDWARE FORMAT.)

  I disagree. RD54's are only supported on the 339/340 ROMs. [Source: DEC-O-LOG
FCO information classifying FCO as "required" if RD54's on RQDX3.]

>    Is there any way to tell the RQDX3 version without physically 
>    examining the drive controller board?

  Yup. The VS2000 doesn't have an RQDX3 8-}. It has logic which is similar
to an RQDX3, but isn't the same. As far as I know, no FCO's to it about this.

>    The XT-1000/2000 Family Disk Drives Quick Reference guide says to
>    jumper between 1 & C for drive zero or between 2 & C for drive one.
>    The RD54 was previously in a MVII as DUA2 with a jumper between 3 & C.
>    (The Micro Systems addendum seems to conflict; which is correct?)

  That's the difference between "physical" address (your drive manual) and
disk unit numbers on the VAX (what Midwest did a bad job of explaining). In
a BA23, the first hard disk is jumpered as drive 3 of 4, and the second as
drive 4 of 4. The floppy drive(s) are 1/4 and (if present) 2/4. The RQDXn
firmware numbers fixed disks first.

  In a BA123 with an M9058 module, normally any drive select will work (this
can be overridden on the M9058).

  I'm not sure about a VS2000. If replacing an existing disk, use the same
setting the old one had. Otherwise try 3/4 for first disk, 4/4 for second.

>    Do I need to reformat the disk?

  No.

>  Is it even safe to do so?

  Not on an out-of-rev RQDX3. Otherwise, yes. However, you will lose the field
bad block history, and you should have the "Field Service" version of the diag-
nostics around just in case.
================================================================================
Note 93.81        Low-end disk devices - The Digital difference        81 of 136
EISNER::KENNEDY "Terry Kennedy"                      17 lines  26-SEP-1991 16:02
                             -< Watch that power! >-
--------------------------------------------------------------------------------
>    The RD54 to be installed already has JE jumpered.  Both the
>    internal RD54 and this new RD54 will be drawing power off the
>    system box (VS2000).  
>
>    Will this JE jumper prevent both drives drawing the huge power
>    surge on startup?  If so, what starts the second drive?  Does
>    the RQDX3 controller automatically handle this, or does some
>    command need to be inserted in the startup procedure?

  I don't believe that pin is controlled by the RQDXn or internal controller.
Thus, it floats high (actually, is terminated high) and both drives start.
Maxtor ships 'em with JE installed.

  I would strongly discourage you from running 2 RD54's off the VS2000 power
supply. I'd suggest you get a PC power supply and a drive power cord exten-
sion and do something that way (you could even get a PC case and mount the
drive (and maybe a TK50?) in it.
================================================================================
Note 93.82        Low-end disk devices - The Digital difference        82 of 136
EISNER::HANRAHAN "Jamie Hanrahan, VMS IntrnlsWkgGrp" 21 lines   1-OCT-1991 01:16
                  -< Let's hear it for "commodity" pricing! >-
--------------------------------------------------------------------------------
> I'd suggest you get a PC power supply and a drive power cord exten-
> sion and do something that way (you could even get a PC case and mount the
> drive (and maybe a TK50?) in it.

I agree... indeed, PC cases and power supplies are so low-priced that one 
should think carefully before doing it any other way! 

I just bought a "midi-tower" case for my 386 system.  6 half-height drive bays,
250 W power supply, excellent cooling, and VERY easy access to the drive
mounting screws, for $125.  And that price was without trying very hard.  (Some
days it's far preferable to throw a few extra bucks at a problem than to spend
time shopping around.) 

At Simpact we had about a dozen PC power supplies "loose" in the R&D lab. These
were used anyplace we needed lots of +5 and +12 and a little bit of -12, which
covers most of the needs in digital electronics these days.  Some of the
prototype PC boards were equipped with suitable Molex connectors so that the PC
power supply could plug right in. Naturally, these connectors were left off the
production boards.  Heck of a lot cheaper than "laboratory" power supplies, or
the typical open-frame and closed- chassis supplies from Lambda, et al. 

================================================================================
Note 93.83        Low-end disk devices - The Digital difference        83 of 136
EISNER::HANRAHAN "Jamie Hanrahan, VMS IntrnlsWkgGrp"  2 lines   2-OCT-1991 19:50
--------------------------------------------------------------------------------
Just what IS the power consumption of an RD54???

================================================================================
Note 93.84        Low-end disk devices - The Digital difference        84 of 136
EISNER::SHUMAKER "Mark L. Shumaker -{The Arachnid}-"  9 lines   3-OCT-1991 10:54
                             -< The survey SAYS: >-
--------------------------------------------------------------------------------
>>  Just what IS the power consumption of an RD54???

An older Systems & Options catalog sez:
 
	5V - 1.3A    12V - 1.34A
 
in the Configuring Info section.  It also says "Power - Max
seeking: 24.0 W" which isn't all that far from the individual
figures (22.58 watts).
================================================================================
Note 93.85        Low-end disk devices - The Digital difference        85 of 136
EISNER::HANRAHAN "Jamie Hanrahan, VMS IntrnlsWkgGrp"  7 lines   3-OCT-1991 13:14
--------------------------------------------------------------------------------
> An older Systems & Options catalog sez:
>  
> 	5V - 1.3A    12V - 1.34A

Interesting.  That's only a little over half as much 12V as the '53!  
How'd they do that?

================================================================================
Note 93.86        Low-end disk devices - The Digital difference        86 of 136
EISNER::KENNEDY "Terry Kennedy"                      10 lines   3-OCT-1991 17:34
                           -< Two things to beware >-
--------------------------------------------------------------------------------
> An older Systems & Options catalog sez:
>  
> 	5V - 1.3A    12V - 1.34A

  2 notes:

  1) That's the "run" current. The "start" current is much higher.

  2) This is valid only for DEC drives (XT-2190D). Regular XT-2190's pull
even more on startup.
================================================================================
Note 93.87        Low-end disk devices - The Digital difference        87 of 136
EISNER::SHUMAKER "Mark L. Shumaker -{The Arachnid}-" 11 lines   4-OCT-1991 11:11
                              -< More on inrush >-
--------------------------------------------------------------------------------
>> 1) That's the "run" current. The "start" current is much higher.

From the same catalog:
 
	Power -- Maximum startup: 66.0 W
	Power -- Maximum seeking: 24.0 W
 
It's hard to say whether the inrush would be equally high for both
5 and 12 V or not.  It does appear that if you're going to put more
than one on a power supply, flanging up some sort of turn-on delay
circuit might be well worthwhile.
================================================================================
Note 93.88        Low-end disk devices - The Digital difference        88 of 136
EISNER::DOW "Bruce Dow, STS Consultants"             27 lines   8-OCT-1991 10:30
                      -< Can't run two RD54s on a VS2000 >-
--------------------------------------------------------------------------------
>	Power -- Maximum startup: 66.0 W
>	Power -- Maximum seeking: 24.0 W
 
> It's hard to say whether the inrush would be equally high for both
> 5 and 12 V or not.  It does appear that if you're going to put more
> than one on a power supply, flanging up some sort of turn-on delay
> circuit might be well worthwhile.
    
    We tried to use an old PC 5151? enclosure and power supply, but
    it didn't have enough juice--the RD54 started knocking.  So, we 
    weren't sure whether the RD54 had been damaged in shipping or if the
    power supply was too weak.  My system manager suggested that I 
    dismount and disconnect the external RD53 on my VS2000 and then 
    plug in the RD54 to see if it still knocked.
    
    Result--it didn't knock...
    
    because the VS2000 stopped dead in its tracks.
    
    So, it definitely appears that a VS2000 does not have enough
    power in the system box to run the system, and two RD54s, even
    on a temporary basis.  After restoring the RD53 and cycling the
    power, the VS2000 works fine.  Meanwhile, I'm being shipped
    a PC/XT box in which the RD54 seems to work fine without knocking.
    

    
================================================================================
Note 93.90        Low-end disk devices - The Digital difference        90 of 136
EISNER::KENNEDY "Terry Kennedy"                       5 lines  16-OCT-1991 20:22
                                -< Micropolis? >-
--------------------------------------------------------------------------------

  I think all the RZ5x are Micropolis drives. Note that the firmware on the
DEC variants is different, though. I have heard that DEC is going to make it
easier to use 3rd-party drives in a future Ultrix Update, by letting you
have complete control over the partitioning and offsets.
================================================================================
Note 93.92        Low-end disk devices - The Digital difference        92 of 136
EISNER::VANMATRE "NSR"                               40 lines  13-NOV-1991 14:42
                          -< More VS3100 ddisk info >-
--------------------------------------------------------------------------------
|>  I think all the RZ5x are Micropolis drives.
|
|Thanks.  Then that would mean:
|
==>	RZ55 = Micropolis 1578-15 or maxtor xt-4380sb2 (332 MB formatted)
|	RZ56 = Micropolis 1588 (665 MB)
|	RZ57 = Micropolis 1598 (1 GB)
|
	A quick look into the dkdriver gives this known drive list. I guess that
if the drive is not listed in the driver then it is a generic drive to the
driver. This is from the 5.4-2 driver I have not seen the 5.4-3 or later
drivers yet. Note the new drives (RZ31...)

Disk	Dec	3rd		3rd
number	drive	party 1		party 2

0	RZ22	Cp350
1	RZ23	Cp3100-1
2	RZ24
3	RZ55	1578-15		XT-4380SB2
4	RRD40	CM 210
6	GENERIC
11	RZ25
12	RZ56
13	RZ57
14	RX23
15	RX33
18	RZ23L
19	RX26
20	RZ57I
21	RZ31
22	RZ58
24	RRD42


	Let's build a master list (as a new note) of the working 3rd party
drives.


Ethan
================================================================================
Note 93.93        Low-end disk devices - The Digital difference        93 of 136
EISNER::LANG                                          4 lines  14-NOV-1991 08:26
                              -< RZ24 Equivalent >-
--------------------------------------------------------------------------------
    
    RZ24 (209 MB formatted) scsi disk drive is connor CP3200.
    
    rml
================================================================================
Note 93.94        Low-end disk devices - The Digital difference        94 of 136
EISNER::BOWEN "Rick Bowen, BPUIG Vice-Chair"          6 lines  16-JAN-1992 14:16
                            -< Is this reasonable >-
--------------------------------------------------------------------------------
If you have an MVII (BA123) with four internal RD53 disk drives is
it possible to replace one of them with an RD54. There are mixed
signals from DEC.

Has anybody run a similar configuration with 4 internal drives and
atleast one of them being a RD54.
================================================================================
Note 93.95        Low-end disk devices - The Digital difference        95 of 136
EISNER::KILGALLEN "Larry Kilgallen"                   9 lines  16-JAN-1992 16:52
                                  -< Power? >-
--------------------------------------------------------------------------------
> If you have an MVII (BA123) with four internal RD53 disk drives is
> it possible to replace one of them with an RD54. There are mixed
> signals from DEC.
> 
> Has anybody run a similar configuration with 4 internal drives and
> atleast one of them being a RD54.

If you also have a TK50, there supposedly is not enough power for 4 disk
drives.  (Yes, I know there are five slots for devices...)
================================================================================
Note 93.96        Low-end disk devices - The Digital difference        96 of 136
EISNER::KOZAM                                        11 lines  16-JAN-1992 21:54
                    -< RD53/RD54 in any combination is OK >-
--------------------------------------------------------------------------------
    Of course Larry Kilgallen is right about power considerations
    (although there are ways to use an external power supply, even if
    the drives themselves are in the BA123).
    
    Another consideration is the controller.  Only RQDX3 controllers can
    be used with RD54 drives.  In addition, older RQDX3 drives need to have
    their firmware upgraded before the RD54s can be used.
    
    With a suitable controller, you can mix and match RD5X/RD3X/RX50/RX33
    drives in any combination you like, as long as no more than four
    logical unit numbers are in use.
================================================================================
Note 93.97        Low-end disk devices - The Digital difference        97 of 136
EISNER::KENNEDY "Terry Kennedy"                      17 lines  17-JAN-1992 02:09
                             -< A few more points >-
--------------------------------------------------------------------------------
>    Of course Larry Kilgallen is right about power considerations
>    (although there are ways to use an external power supply, even if
>    the drives themselves are in the BA123).
    
  Right. The best thing to do it to look in the BA123 manual and add up your
power requirements. Frequently you can rearrange things by moving power-hungry
boards 1 slot (since each slot alternates power supplies). Also, note that one
of the disk/tape power cables has 3 connectors and the other has 2. Be sure 
you know which supply each is going to.

>    Another consideration is the controller.  Only RQDX3 controllers can
>    be used with RD54 drives.  In addition, older RQDX3 drives need to have
>    their firmware upgraded before the RD54s can be used.
 
  Minor nit - all revs of the RQDX3 firmware support the RD54. However, there
is a jumper that needs to be inserted on older boards. Also, older boards can't
successfully format the RD54. I believe the latest firmware is 339/340.
================================================================================
Note 93.98        Low-end disk devices - The Digital difference        98 of 136
EISNER::KENNEDY "Terry Kennedy"                       4 lines  17-JAN-1992 02:11
               -< Also, be sure you have the wiring harness FCO >-
--------------------------------------------------------------------------------
  Oops - I almost forgot. Be _SURE_ you have the new-style power harnesses
installed (individual wires in white connectors). The old-style harnesses
(duck-foot webbed cable *or* individual wires in yellow connectors) _WILL_
cause a fire in your cabinet at some point.
================================================================================
Note 93.99        Low-end disk devices - The Digital difference        99 of 136
EISNER::LEDERMAN "Bart Z. Lederman"                  44 lines  24-FEB-1992 10:13
            -< Second MAXSTOR drive on ??? EDSI controller problem >-
--------------------------------------------------------------------------------
    We've run into a problem here, and I hope someone can recognize what it
    is.

    We have a MVII in a BA23 box which was transferred from another agency
    with no documentation.  It's been working fine for some time.

    It has a third-party disk controller: there is no manufacturer's name on
    it, but it says SCD-RQD11/EC on it.  One of the ROMs has a paper label
    saying RQD11EC
           CBDI V2.39

    and it has two 4-position DIP switches and one 10 position switch.
    It is apparently an EDSI controller, because we have one MAXSTOR
    XT-8760E 760 MB drive hooked up to it.  With one drive connected, it
    works just fine.

    We would like to hook up a second MAXSTOR drive (we took out the TK50
    to make room).  Power doesn't seem to be a problem.

    The second drive was previously used on this system, and has VMS on it.

    If I plug in just one drive (either one), it works fine.

    When I plugged in both drives and tried to boot, the drive active lights
    came on on both drives.  This really wasn't surprising.

    We obtained the documentation on the drive through the MAXFAX line
    (thanks to whoever posted that here, by the way).  I moved the unit
    select plug (I think) on one drive from DS1 to DS2.  Now, if I have
    both drives plugged in and try to boot, only the "DUA0" drive (the one
    with the plug in DS1) is accessed, and it boots fine.  BUT: neither the
    boot ROM nor the operating system can see the other drive (the one with
    the jumper in DS2).  Moving the jumper to DS3 makes no difference. 
    Moving the jumper back to DS1 and moving the jumper on the other drive
    to DS2 moves the problem to the other drive.  Moving the cables between
    drives makes no difference.

    Does anyone know how I get this controller to recognize two drives?

    The controller has one big jack for the data cable, four jacks for the
    unit control cables, and one jack of unknown use with nothing plugged
    in.  The cables go directly from the controller to the drives, and do
    not go though the BA23 distribution panel or front panel switches.
    
================================================================================
Note 93.100       Low-end disk devices - The Digital difference       100 of 136
EISNER::YOUDELMAN "Billy Y"                           9 lines  24-FEB-1992 11:22
--------------------------------------------------------------------------------

>    it, but it says SCD-RQD11/EC on it.

This sounds like a Sigma Controller (SDC-..), which will need to to be told
about the drive and etc.  The ten-pin Berg connector accepts a terminal (same
pin-out as connectors on a DLV-11J) that can do this, or it can talked to
thru the bus.  I don't have docs for this particular controller, try calling
Sigma Information Systems in Las Vegas, 702 597-1072.

================================================================================
Note 93.101       Low-end disk devices - The Digital difference       101 of 136
EISNER::KENNEDY "Terry Kennedy"                      34 lines  24-FEB-1992 13:53
                         -< Hopefully this will help >-
--------------------------------------------------------------------------------
>    It has a third-party disk controller: there is no manufacturer's name on
>    it, but it says SCD-RQD11/EC on it.  One of the ROMs has a paper label
>    saying RQD11EC
>           CBDI V2.39

  Sounds like a Sigma. They relabel Webster controllers - I beleive the
controller is a WQESD/4.

>    and it has two 4-position DIP switches and one 10 position switch.
>    It is apparently an EDSI controller, because we have one MAXSTOR
>    XT-8760E 760 MB drive hooked up to it.  With one drive connected, it
>    works just fine.

  The 8760E is an ESDI drive.

>    Does anyone know how I get this controller to recognize two drives?

  See below.

>    The controller has one big jack for the data cable, four jacks for the
>    unit control cables, and one jack of unknown use with nothing plugged
>    in.  The cables go directly from the controller to the drives, and do
>    not go though the BA23 distribution panel or front panel switches.
    
  The other connector is an RS-232 line (sort of) with a similar pinout to
the DLV11-J connector. It speaks 9600 baud but there is usually an incan-
tation to wake it up. The Webster version also has a way to talk to it via
the MV console using some deposit commands to set up a data path and start
the firmware.

  If this is like the Webster, then you need to tell it that the new drive
is MSCP unit #1. MSCP unit numbers have nothing to do with the physical
drive select (although you do need different numbers there as well). The
Webster version has a "change unit number" option on the menu.
================================================================================
Note 93.102       Low-end disk devices - The Digital difference       102 of 136
EISNER::LEDERMAN "Bart Z. Lederman"                  19 lines  24-FEB-1992 14:03
                    -< Making progress: need cable pinout. >-
--------------------------------------------------------------------------------
    
    Thanks very much for the information. It has helped already.
    
    So far, nobody answers the telephone at the Las Vegas number for Sigma. 
    If anyone has any alternate numbers for them or for Webster, I'd
    appreciate having them.
    
    Also: I've dug up a ribbon cable with an 8 pin connector at one end. 
    I'd like to put a connector at the other end so I can hook up a
    terminal.  I do not have a DLV11-J or other device to copy from (the
    cable for the console terminal on a MVII is 8 pin but has one pin
    "blanked out" to key it, so I can't use that as a template).  If anyone
    has the pin connections for the cable for this controller or a DLV11-J,
    I'd really appreciate having that as well.
    
    If you have it, you might want to post it in note 14, where the DLV11
    is already discussed.
    
    Thanks again.
================================================================================
Note 93.103       Low-end disk devices - The Digital difference       103 of 136
EISNER::YOUDELMAN "Billy Y"                          31 lines  24-FEB-1992 14:56
--------------------------------------------------------------------------------

Well, I have the dual-wide version of this controller, which is sort of
the same except for no cache and only supports two drives.  Its docs call
that 10-pin Berg the "RS-232 Maintenance Terminal" port, which uses 9600,
8N.  It further says if a VT-220 nis sed it must be set for space parity
rather than no parity.

They describe an adapter cable which does this:

Controller      DB-25S
   7              7     RS232 enable
   8              2     Input data
   3              3     Output data
   4              7     Ground

And it says "if normal disk access is attempted while this cable is plugged
in garbage will appear on the terminal due to the shared RS-232 Output/Access
Light Function.  This is normal."

What should be easier than a seperate cable or terminal is, if you are booting
from this guy, is to type a return on the console before it automatically
starts the boot (there's a couple secs after it first signs on to allow for
this) then enter W (for Wombat, the name of their little setup program),
after which there are short menus.

To enable the "maintenance terminal" there are either switches of the board,
or you can use ODT and stuff 260 into the IP register (again here, docs are
necessary).

Another number to try for Sigma:  702 597-5111.

================================================================================
Note 93.104       Low-end disk devices - The Digital difference       104 of 136
EISNER::LEDERMAN "Bart Z. Lederman"                  15 lines  24-FEB-1992 18:18
               -< Making some progress: right telephone number. >-
--------------------------------------------------------------------------------
| thru the bus.  I don't have docs for this particular controller, try calling
| Sigma Information Systems in Las Vegas, 702 597-1072.
    
    I finally figured out that I should call Information, and found that
    the number is 702-597-0172.  I guess two digits got exchanged
    inadvertently.
    
    I called and talked to their technical support.  They seem fairly
    friendly.  They gave me instructions for booting their monitor /
    diagnostic program, but so far it hasn't worked.  They are researching
    the problem and will get back to me.  I'll probably try the terminal
    interface tomorrow.  When I have something that works I'll post it
    here.
    
    Thanks for the help.
================================================================================
Note 93.105       Low-end disk devices - The Digital difference       105 of 136
EISNER::LEDERMAN "Bart Z. Lederman"                  14 lines  26-FEB-1992 12:17
                          -< Drives are working now. >-
--------------------------------------------------------------------------------
    Well, we never did figure out why the diagnostic program didn't boot. 
    But I did hook up a terminal to the auxiliary port, stuff in the
    command to tell the controller to talk to that port (has to be done
    from the console), and had the monitor program come up.  At that point,
    configuration was very easy.  It's all menu driven, the drive had been
    used on the controller before so it was able to sense the drive
    characteristics; all I had to do was tell it that the drive should be
    assigned to unit 1.  Both the Micro-VAX II boot ROM and the VMS
    operating system see both drives now.
    
    I am fairly well satisfied with the support I received from Sigma over
    the telephone, and would consider them for future purchases.  We are
    also happy with the Maxstor drives and their faxsimile information
    service, and would certainly consider them in the future as well.
================================================================================
Note 93.106       Low-end disk devices - The Digital difference       106 of 136
EISNER::BURNET "John Burnet"                         36 lines   6-JUN-1992 18:40
                    -< DEC/3rd-party SCSI disk drive list >-
--------------------------------------------------------------------------------
Here's an updated SCSI drive list, compiled from 93.92 and following notes,
and reflecting the drive-type table in the VMS V5.5 DKDRIVER.  (Note the
new "L" drives at the end, and also the RZ72/73 and RZ31/35.)  Not all of
the 3rd-party names shown below actually appear in the table in DKDRIVER.

Please fill in the blanks if you can.

Disk	DEC	3rd			3rd
number	drive	party 1			party 2

0	RZ22	Cp350    (Conner)
1	RZ23	Cp3100-1 (Conner)
2	RZ24	Cp3200
3	RZ55	1578-15	 (Micropolis)	XT-4380SB2 (Maxtor)
4	RRD40	CM 210   (LMS)
6	GENERIC
11	RZ25
12	RZ56	1588     (Micropolis)
13	RZ57	1598     (Micropolis)
14	RX23
15	RX33
18	RZ23L
19	RX26
20	RZ57I
21	RZ31
22	RZ58	1908     (Micropolis)
23      RWZ01
24	RRD42	CDU-541  (Sony; CDU-6211 includes case & ps)
36      RZ72
37      RZ73
38      RZ35
39      RZ24L   LPS-240S (Quantum) [??? -- not confirmed]
40      RZ25L
41      RZ55L
42      RZ56L
43      RZ57L
================================================================================
Note 93.107       Low-end disk devices - The Digital difference       107 of 136
EISNER::MAYHEW "Bill, Business Practices SSG Chair"  29 lines  25-JUN-1992 19:05
                           -< Pricing: DEC vs. DEC >-
--------------------------------------------------------------------------------
    Suppose one wanted to buy DEC-labeled SCSI disks but was disinterested 
    in RZ2x pricing.  What's the difference between the SCSI disks DEC
    sells for the DECpcs and the RZ2x models?
    
    What drew my attention to this was the PCXAR-AG, a 245MB disk with a
    list of $650, vs. the RZ24L with a list of $1500.  The extended
    description on the Electronic Connection even says the PCXAR-AG is a
    "replacement" for the RZ24L-E.
    
    Here's a complete list of the comparisons that look interesting.
    
    DECpc model & capacity  Price	VAX model & capacity	Price
    
    PCXAR-AA, 200MB	    $930	RZ24, 209MB		$1500
    PCXAR-AB, 426MB	    $1727	RZ25, 426MB		$2250
    PCXAR-AC, 852MB	    $2656	RZ26, 1050MB*		$29xx
    PCXAR-AG, 245MB	    $650	RZ24L, 245MB		$1500
    
    *Note that there's a significant capacity difference here.  The 852MB
    in the PC version is comparable to the RF35 Larry Kilgallen mentioned
    in <some-other-topic>.
    
    I guess my questions are:
    	a. Is there any functional difference between the items on the left
    	   and the items on the right;
    	b. If one bought the items on the left for a VAX, would DEC service
    	   it?
        c. What would VMS recognize the items on the left as?  (OK, this is
    	   a subset of question a.)
================================================================================
Note 93.108       Low-end disk devices - The Digital difference       108 of 136
EISNER::KENNEDY "Terry Kennedy"                      25 lines  25-JUN-1992 22:47
                             -< Non-answer answer >-
--------------------------------------------------------------------------------
>    Suppose one wanted to buy DEC-labeled SCSI disks but was disinterested 
>    in RZ2x pricing.  What's the difference between the SCSI disks DEC
>    sells for the DECpcs and the RZ2x models?
    
  SIde comment: Not all of the identical-lloking items are identical. As an
example, the VRT19 monitors appear to be orderable at a much lower cost via
PCBYDEC. However, they're the older -Cx version, not the improved -Hx type.

>    	a. Is there any functional difference between the items on the left
>    	   and the items on the right;

  I think you'll have to try them to find out. I suspect the mounting hard-
ware will be different, at the very least.

>    	b. If one bought the items on the left for a VAX, would DEC service
>    	   it?

  I think that's a branch-by-branch call. You could certainly put them on
as two line items, one for a VAX and one for a PC peripheral. The only place
you might get bit is troubleshooting.

>        c. What would VMS recognize the items on the left as?  (OK, this is
>    	   a subset of question a.)

  Worst case, "generic SCSI disk". They still work...
================================================================================
Note 93.109       Low-end disk devices - The Digital difference       109 of 136
EISNER::KOSKOVICH "Bob K / BPSSG DECUServe Monitor"  25 lines  13-OCT-1992 21:16
                  -< Still confused about DEC vs 3P SCSI... >-
--------------------------------------------------------------------------------
> Disk		DEC	3rd			3rd
> number	drive	party 1			party 2

> 22		RZ58	1908     (Micropolis)
    
    
    I have a few questions about the info in this topic.  I hope one of you
    gurus can be of assistance!
    
    Does this mean that I can buy a vanilla Micropolis 1908, and when it
    ends up on the SCSI bus, the VAX will think it's an RZ58, no questions
    asked?  Or will it still show up as "generic"?
    
    The Systems & Options catalog gives a wonderful table of all the
    "features" of Digital's RZ drives.  Is there any merit to this list? 
    Are the features part of the OEM disk, or is some sort of additional
    Digital "blessing" given to it?
    
    How does Digital maintain this?  Is there a "FS-" part number or would
    they call it an RZ58?
    
    Will this fit right into my BA42 (SZ12C-XA) box?
    
    Finally (only partly-related):  Will VMS 5.4 support the RZ58?  (Just a
    matter of when I upgrade to 5.5 vs. when I buy the disk!)
================================================================================
Note 93.110       Low-end disk devices - The Digital difference       110 of 136
EISNER::BURNET "John Burnet"                         54 lines  14-OCT-1992 06:49
                  -< Go for it, and save yourself some cash >-
--------------------------------------------------------------------------------
[This is a re-posting... the original reply that I posted last night
had a couple of errors regarding VMS support for the RZ58.]

>   <<< Note 93.109 by EISNER::KOSKOVICH "Bob K / BPSSG DECUServe Monitor" >>>
>
>    I have a few questions about the info in this topic.  I hope one of you
>    gurus can be of assistance!

I don't claim to be one, but I think I can help anyway.  :-)
    
>    Does this mean that I can buy a vanilla Micropolis 1908, and when it
>    ends up on the SCSI bus, the VAX will think it's an RZ58, no questions
>    asked?  Or will it still show up as "generic"?

It will still show up as "Generic SCSI disk".  DEC changes the vendor
and drive IDs in the firmware.
    
>    The Systems & Options catalog gives a wonderful table of all the
>    "features" of Digital's RZ drives.  Is there any merit to this list? 
>    Are the features part of the OEM disk, or is some sort of additional
>    Digital "blessing" given to it?

If you mean the comparison chart (on page 7.6 of the July 1992 edition),
the performance features are characteristics of the raw drives.  The only
thing that I'm aware of that can change due to DEC's modifications is the
formatted capacity: DEC might allocate more sectors per track for bad-block
replacement, reducing the capacity very slightly.
    
>    How does Digital maintain this?  Is there a "FS-" part number or would
>    they call it an RZ58?

They won't call it an RZ58, and you will pay slightly more per month
than you would pay for maintenance of an RZ58.
    
>    Will this fit right into my BA42 (SZ12C-XA) box?

Yep... if an RZ58 will, a 1908 will.
    
>    Finally (only partly-related):  Will VMS 5.4 support the RZ58?  (Just a
>    matter of when I upgrade to 5.5 vs. when I buy the disk!)

Maybe not.  The chart in the S & O Catalog says that 5.5 is the minimum
VMS version required.  I don't know what that means exactly (i.e., what
feature is present in 5.5 but absent from previous versions).

Also, please see note 795.11 in this conference if you plan to use
the disk on a VS3100 or MV3100.

One additional item:  According to topic 908 here, Ultrix has (or at least had)
a misfeature that would cause non-DEC disks to be used only in async mode,
limiting their throughput.  If you'll only be using VMS, that won't matter
to you.  The older VS3100/MV3100 systems that use the NCR 5380 chip can
only do async transfers anyway, so if you're using one of those you won't
see the maximum performance even with VMS.
================================================================================
Note 93.111       Low-end disk devices - The Digital difference       111 of 136
EISNER::KOSKOVICH "Bob K / BPSSG DECUServe Monitor"  45 lines  15-OCT-1992 02:05
                           -< Thanks for the info! >-
--------------------------------------------------------------------------------
> >    The Systems & Options catalog gives a wonderful table of all the
> >    "features" of Digital's RZ drives.  Is there any merit to this list? 
> >    Are the features part of the OEM disk, or is some sort of additional
> >    Digital "blessing" given to it?
> 
> If you mean the comparison chart (on page 7.6 of the July 1992 edition),
> the performance features are characteristics of the raw drives.
    
    Actually, I was referring to the features listed on page 7.59-60, like:
    
      * elevated shock, vibration, and temperature specifications...
      * on power failure, writes-in-progress are completed...
      * all errors, hard and soft, are reported to the system...
      * ...overlapped seeking...
    
> >    How does Digital maintain this?  Is there a "FS-" part number or would
> >    they call it an RZ58?
> 
> They won't call it an RZ58, and you will pay slightly more per month
> than you would pay for maintenance of an RZ58.
    
    That's what I figured.  I thought I saw a suspicious looking
    "FS-MCP..." number in the price list.
    
> The chart in the S & O Catalog says that 5.5 is the minimum
> VMS version required.  I don't know what that means exactly (i.e., what
> feature is present in 5.5 but absent from previous versions).

    Had I seen that table earlier, I wouldn't have asked!  I'll do some
    checking elsewhere about just what it means that the RZ58 needs 5.5.
    
> Also, please see note 795.11 in this conference if you plan to use
> the disk on a VS3100 or MV3100.

    Thanks for the cross-reference.  I'm not going to be using this as a
    system disk, so from the sound of that note, I'm OK.
    
> The older VS3100/MV3100 systems that use the NCR 5380 chip can
> only do async transfers anyway, so if you're using one of those you won't
> see the maximum performance even with VMS.
    
    Hmm... would a MV3100/10e qualify as an "older" system?  :-)
    
    Trust me, with a 10e, I'm accustomed to not seeing "maximum
    performance"!
================================================================================
Note 93.112       Low-end disk devices - The Digital difference       112 of 136
EISNER::BURNET "John Burnet"                         19 lines  15-OCT-1992 04:17
           -< The 1908's performance might be wasted on a 10e  :-( >-
--------------------------------------------------------------------------------
>   <<< Note 93.111 by EISNER::KOSKOVICH "Bob K / BPSSG DECUServe Monitor" >>>
>    
>    Actually, I was referring to the features listed on page 7.59-60, like:
>    
>      * elevated shock, vibration, and temperature specifications...
>      * on power failure, writes-in-progress are completed...
>      * all errors, hard and soft, are reported to the system...
>      * ...overlapped seeking...

Also 48-bit ECC, and 90% coverage by the power-up self-tests, including
write & read diags.  Sorry, I don't know how many of those features are
from Micropolis and how many are from DEC.  Can anyone else help?
For what it's worth, I'm posting a partial, preliminary data sheet
from Micropolis's BBS in the next reply.  (The BBS # is 818-709-3310.)
    
>    Hmm... would a MV3100/10e qualify as an "older" system?  :-)
    
Unfortunately, yes... that's one with the 5380.  The MV3100/30, /40,
/80, and /90 have a sync-SCSI chip.
================================================================================
Note 93.113       Low-end disk devices - The Digital difference       113 of 136
EISNER::BURNET "John Burnet"                        194 lines  15-OCT-1992 04:02
          -< Data sheet for Micropolis 1908, courtesy of Micropolis >-
--------------------------------------------------------------------------------
                  MICROPOLIS 1908 DISK DRIVE
                        SPECIFICATIONS

                                       Model Number
Unformatted Capacity:                   1908-15 

Total Mbytes            --------------  1600 -----------------       
Disk Platters           ------------------ 8 -----------------       
Read/Write Heads        ----------------- 15 -----------------        
Cylinders               --------------- 2112 -----------------        
Bytes per track         -------------- VARIABLE -------------- 

Formatted Capacity  

Total Mbytes            --------------- 1381 -----------------        
Bytes per Sector        ---------------- 512 -----------------        
Sectors per Track       -------------- VARIABLE -------------- 

PC Setup

  When using SCSI in a PC, the most common method is to run your       
  setup program and define No Drives Present. The SCSI Host Adapter    
  will automatically self-configure on power-up. To install the        
  drive, follow the manufacturer's instructions to use the on-board    
  BIOS routine or software that was supplied with the Host Adapter.   

Performance Specifications  

  Seek Time                       Adjacent Track         2.5 msec
    (including settling time)     Average               11.5 msec
                                  Maximum                 25 msec

  Average Rotational Latency                            5.56 msec
  Rotational Speed                              5400 rpm +/- 0.5%

  Data Transfer Rate at Interface  
     Synchronous                              Up to 10 Mbytes/sec
     Asynchronous                             Up to  4 Mbytes/sec

  Internal Data Rate                                30 to 40 MHz

  MTBF                                              150,000 hours
  Positioner                     Fully balanced rotary voice coil
  Parking                                 Automatic park and lock

 General Functional Specifications  

  Interface                                                SCSI-2
  Supports Full Common Command Set                            YES
  Mounting Plane                                  Any orientation

Power Requirements  

  +12V +/-5%                                            2.0A  Avg
                                       (4.3A max during start-up)
  +5V +/-5%                                              1.5A avg
 
  Power dissipation, typical                             24 Watts
 
 
7. Drive Addressing and Interface Termination


         ___________Slave sync(pin 20)
        |   ________Master sync(pin 16)
        |  |  ______Bus parity check option( 7th set of  pins) 
        |  | | _____Write protect option(6th set of pins)
        |  | || ____Spindle control option(4th set of pins)
        |  | ||| ___ID2    
        |  | |||| __ID1        
        |  | ||||| _ID0                    Pin 1  
        |  | ||||||                             |             
        ___________    __________________________     ________  
      _|    J2     |  |          J1              |   |   J3   |  
     | |___________|_ |__________________________|___|________|  
     |                                                        |  
     |                       W12 :    ___________  . W1       |  
     |                               |___________| : W2       |  
     |                                 RN6                    |  
     |                                                    W11 |  
     |                                                        |  
     |                                                        |  
     |                                                        |  
     |                                                        |  
     |                                                        |  
     |                                 Component Side         |  
     |                                                        |  
 
 
ID0, ID1, ID2 SCSI Address Jumpers  
  The SCSI ID (drive address) jumpers are identified as ID0, ID1, 
  and ID2. ID selection is binary, as shown in the table below.  
 
   SCSI              Jumpers  
  Address        ID2   ID1   ID0  
  -------        ---   ---   ---  
     0           out   out   out  
     1           out   out    in  
     2           out    in   out  
     3           out    in    in  
     4            in   out   out  
     5            in   out    in  
     6            in    in   out  
     7            in    in    in  
  
  For multiple drive installations, on one Host Adapter, each drive 
  must have a unique address. Drives are configured as SCSI ID 7 
  at the factory.  
 
RN6 Interface Terminator  
  The Interface Terminator factory installed at RN6 provides     
  proper termination for the interface lines. When daisy-chaining  
  multiple drives, leave the terminator installed only in the last 
  physical drive (or drives) on the daisy chain cable; remove the 
  terminator from each of the other drives (or the host computer). 
 
Bus Termination Power Option  
  A jumper is installed at W1, at W2, or at W2 and W12 to select the   
  source of terminator power (+5V) for the SCSI Bus terminator packs on 
  the device electronics board.

  DO NOT INSTALL JUMPERS AT BOTH W1 AND W12

  When a jumper is installed at W1(the factory default configuration), 
  the drive provides terminator power to it's on-board terminators.

  When  a jumper is installed at W2 , terminator power is is provided by 
  the host system via the interface cable J1, pin 26 (TERMPWR).

  When a jumper is installl at both W2 and W12, the drive provides     
  terminator power to its on-board terminators and also to the SCSI bus 
  via interface cable J1,pin 26(TERMPWR).

Frame Ground Options  
  Jumper W11 selects the frame ground option.

  When W11 is installed, the drive's frame is connected to frame ground.

  When a jumper is not installed at W11 (the factory default
  configuration), frame ground is not connected to logic ground.

Spindle Control Options
  A jumper bridging pins 7 and 8 of J2 (the 4th set of pins)is used to 
  select the spindle control option.

  When a jumper is installed, the drive must wait for an interface Start 
  Unit command to start the spindle motor.

  When a jumper is not installed(the factory default configuration),   
  the drive automatically starts the spindle motor at power-on

Write Protect Option
  A jumper bridging pins 11 and 12 of J2 (the 6th set of pins) is used 
  to select the write protect option.

  When a jumper is installed, the drive is write protected. CAUTION: The 
  drive can still be formatted.

  When a jumper is not installed,(the factory default configuration),  
  the drive is not write protected.

Bus Parity Option
  A jumper bridging pins 13 and 14 of J2(7th set of pins) is used to   
  select the parity check option.

  When a jumper is installed, the drive neither generates nor detects  
   parity.

  When a jumper is not installed,(the factory default configuration),the 
  drive generates parity and enables parity detection.

Spindle Synchronization Option
  The Rotational Position Locking field(MODE SELECT command, Page Code 
  04h) is used to specify spindle synchronization operation; see       
  document #110366(Scsi Implementation in Micropolis "MZR" Products) and 
  ANSI SCSI Standard.

  Unsynchronized:If the drive is est to Unsynchronized(PRL=00b), it    
  ignores the SLAVE SYNC signal.

  Slave:If the drive is set to Slave(RPL=01b), it does not generate the 
  MASTER SYNC  signal or the SLAVE SYNC signal but synchronizes its    
  index to the SLAVE SYNC signal (J2,pin 20) supplied by an external   
  source

  Master:If the drive is set to MASTER(RPL=10b), it generates the SLAVE 
  SYNC output signal (j2,pin 20) for use directly by the slave drives.

  Master Control:If the drive is set to Master Control(RPL=11b), i     
  generates the MASTER SYNC signal(j2,pin 20). This output is used by  
  the controller to generate the SLAVE SYNC signal(J2,pin 20) for the  
  slave drives.

  **** THESE SPECIFICATIONS ARE PRELIMINARY.
================================================================================
Note 93.114       Low-end disk devices - The Digital difference       114 of 136
EISNER::HANRAHAN "Jamie Hanrahan, VMS IntrnlsWkgGrp"  4 lines   1-JAN-1993 22:54
                          -< RD53 won't stay spun-up >-
--------------------------------------------------------------------------------
I have a pair of RD53s (real, labelled-as-RD53's) which seem to spin up 
normally, but then spin back down again.  Could this be due to a jumper
or other "configurable" setting?  What could cause this?

================================================================================
Note 93.115       Low-end disk devices - The Digital difference       115 of 136
EISNER::HANRAHAN "Jamie Hanrahan, VMS IntrnlsWkgGrp" 20 lines   3-JAN-1993 18:06
                   -< RD53s won't stay spun-up (more info) >-
--------------------------------------------------------------------------------
My previous note on this topic did not give enough information. 

These RD53s both worked on an RQDX3.  They've been sitting idle for some time.
I decided to try selling them as PC disks but first I thoughtI'd better check
them out on a PC.  I pulled the R7 jumpers on both.  One of them formatted
just fine, but then started showing this "won't stay spinning" symptom.  
The other did the same thing before I tried formatting it. 

I put the R7 jumpers back in and tried the drives back on the RQDX3...
and they did the same thing.

I checked the power with a DMM during spin-up; nothing unusual.  Both of
the power supplies (PC and BA123) have been happily spinning two drives 
apiece for some time now.  

I can't help thinking that I "bumped something" during the jumper change.
Would could it be?  What will make an RD53 do this?  

(As an aside, just what does that R7 jumper do anyway?  I got mail from one
person who said that he had used RD53s on PCs without removing R7.)
================================================================================
Note 93.116       Low-end disk devices - The Digital difference       116 of 136
EISNER::MCINTYRE "Tom McIntyre"                      13 lines   3-JAN-1993 23:50
                          -< jumper is unit address >-
--------------------------------------------------------------------------------
    Not having a disk in front of me, R7 doesn't mean much.  However, the
    jumpers near the connectors at the back of the drive are address
    jumpers and control whether the drive is unit 0 etc.  I believe the
    RQDX3 wants them to be unit 4 and that PCs want them to be unit 0. 
    Most PCs seem to do unit select on mfm drives by twisting the cable.
    
    The behavior sounds like power or some other servo interlock.  Perhaps
    something got bumped when you took off the sliders.  In my experience
    it does not take much to give these guys a head crash either.  A 2 or 3
    inch drop onto a work table can do it.
    
    We have put 5 or 6 of them into PCs and have lost 2 to head crashes
    while "sitting on the shelf."
================================================================================
Note 93.117       Low-end disk devices - The Digital difference       117 of 136
EISNER::KENNEDY "Terry Kennedy"                      12 lines   4-JAN-1993 08:19
                                -< More on R7 >-
--------------------------------------------------------------------------------
> (As an aside, just what does that R7 jumper do anyway?  I got mail from one
> person who said that he had used RD53s on PCs without removing R7.)

  R7 makes the drive misbehave so DEC can tell the difference between it and
an RD52. Really. Whether the drive works or not on a PC with R7 still in de-
pends on the PC controller. A lot of cheap imported MFM controllers will be
quite happy with it in. Things like Adaptec controllers will give you a 1701
error if it's in.

  As far as your spinup/down problem, I'd make sure that you didn't dislodge
any of the ribbon cables between the logic board and the drive (there's a
set of 3 brown cables, as I recall)
================================================================================
Note 93.118       Low-end disk devices - The Digital difference       118 of 136
EISNER::KOZAM                                         5 lines   7-JAN-1993 21:52
                       -< Controller signal to spin up? >-
--------------------------------------------------------------------------------
    Do the drives still work with an RQDX3?  Funny that two drives should
    fail simultaneously, however.
    
    I vaguely remember some signal on the 34 pin connector that instructs
    drives to spin up.  Perhaps this only applies to the floppy, however.
================================================================================
Note 93.119       Low-end disk devices - The Digital difference       119 of 136
EISNER::HANRAHAN "Jamie Hanrahan, VMS IntrnlsWkgGrp" 11 lines   8-JAN-1993 01:40
--------------------------------------------------------------------------------
>     Do the drives still work with an RQDX3?  Funny that two drives should
>     fail simultaneously, however.

They used to.  They had been working on an RQDX3, were taken out of service
and have been sitting on the shelf for a few months.
    
>     I vaguely remember some signal on the 34 pin connector that instructs
>     drives to spin up.  Perhaps this only applies to the floppy, however.

Don't think so -- the RDxx hard drives of my acquaintance always spin up when
the box is powered on.  
================================================================================
Note 93.120       Low-end disk devices - The Digital difference       120 of 136
EISNER::LEDERMAN "Bart Z. Lederman"                  12 lines  27-FEB-1993 17:42
                       -< Anything larger than an RD54? >-
--------------------------------------------------------------------------------
    As I mentioned elsewhere in this conference, I'm putting together a
    MicroVAX-II with old parts.  I now have an RD52 running on an RQDX3
    controller.  I've been through this note stream and some others, and
    don't see any mention of a disk drive with more capacity than the RD52
    that would run on this controller.
    
    Were there ever any disk drives which store more than an RD54 (159 MB)
    which I can plug into this controller from DEC?  How about from
    third-parties, or directly from Disk manufactuers?
    
    (Note that I don't have diagnostics for this system, so I don't know
    how I'd format the drive if it needed it.)
================================================================================
Note 93.121       Low-end disk devices - The Digital difference       121 of 136
EISNER::KENNEDY "Terry Kennedy"                      14 lines  27-FEB-1993 17:56
                               -< Sorry, but no >-
--------------------------------------------------------------------------------
>     Were there ever any disk drives which store more than an RD54 (159 MB)
>     which I can plug into this controller from DEC?  How about from
>     third-parties, or directly from Disk manufactuers?

  Nope. Aside from the lack of interest in producing MFM/ST-506 drives these
days, you have 3 areas to grow: cylinders, heads, and sectors. The RD54 has
1226 cylinders (1224 usable), which is about the limit, 16 heads (1 for servo),
likewise, and 17 sectors/track, which is an MFM requirement. Of these, the
easiest to increase is sectors/track, but that means a higher bit rate and a
different interface format.

  If you need more/faster storage, I suggest you go SCSI. You can get a 1.6Gb
Seagate (ST41600N) for about $1800 new. Add a CMD/Dilog/Emulex controller to
that. The combo will cost less than an RD54 new-from-DEC.
================================================================================
Note 93.122       Low-end disk devices - The Digital difference       122 of 136
EISNER::LEDERMAN "Bart Z. Lederman"                    1 line  28-FEB-1993 08:19
                        -< Thanks for the informatin. >-
--------------------------------------------------------------------------------
    
================================================================================
Note 93.123       Low-end disk devices - The Digital difference       123 of 136
EISNER::MCINTYRE "Tom McIntyre"                       4 lines   1-MAR-1993 23:20
                                  -< DSP3105 >-
--------------------------------------------------------------------------------
    The DEC DSP3105 is $1620 list from desktop direct and works just fine
    with the CMD controller.  I have also seen brandless 1 GByte drives for
    $800.  The 3105 is 9 msec average access also which is kind of nice and
    pulls almost no power from your poor starved BA23. :-)
================================================================================
Note 93.124       Low-end disk devices - The Digital difference       124 of 136
EISNER::WALLACE                                      41 lines  11-MAR-1993 21:32
                     -< Large MFM / RQDX3 Ramblings .... >-
--------------------------------------------------------------------------------
    	The Maxtor 2190 (RD54) or the Priam 519 or Storage Dimensions
    AT-160, all of which had the same geometry were pretty much the "max"
    as far as large MFM drives went.  In some cases, there were "RLL"
    variants of these drives, which would format to about 240 MB, but this
    coding is not supported by the RQDX3.
    
    	Sigma (and possibly others) did make a Q-bus controller that "talked
    MSCP" on the Q-bus side and ST-506/RLL on the drive interface.  If you
    could find one of these at a 'give-away' price, and wanted to live
    dangerously, you could format an RD-54 RLL.  Internet news has had some
    postings from folks who claim success with this trick, but it is risky.
    
    	If you want to try RD-53's or RD-54's, note that the E-store is showing 
    B2-RD53-AA at $195, and B2-RD54-AA at $495.  These are refurbished, but
    the usual deal with "B2" refurbs is that they carry a new product warranty 
    -- typically "1 year return to DEC" for items in this class.
    
    	The RQDX3 logic supports a "maximum" MFM drive configuration of 16 data
    heads and 2048 cylinders, with 17 sectors per track, which works out to
    280+ MB in a single unit.  While some of the newer drives have this
    many cylinders (in 2.5" format!), the maximum I've run across for an
    MFM drive is 1314, in the Microscience 1090HH.  
    
    	The Microscience drive is a possibility -- it is a 5.25" HH unit
    that will format to 71 MB right out of the box on an RQDX3 running the
    ZRQCH0 XXDP formatter on a PDP-11.  Simply select the "RD33" drive from
    the menu, with "Continue if bad block information is unavailable". 
    This format uses 1170 of the available 1314 cylinders.  The full capacity
    of the drive (79.7 MB formatted) can be realized by loading the ZRQCH0
    program, and before issuing "start" from the DR> prompt, entering console
    ODT to patch the RD33 parameter table to the values correct for the
    Microscience drive.  I've got two of them running happily with this
    patch.
    
    	Best long term prospects for the older Q-bus systems would be to
    "go SCSI" as Terry suggests, but this gets to be a $1-2 K proposition
    as a minimum if you buy "new" (drive with controller), and this may be
    a bit 'off scale' for an at home hobby project.
    
                                            Roger Wallace
     
================================================================================
Note 93.125       Low-end disk devices - The Digital difference       125 of 136
EISNER::KENNEDY "Terry Kennedy"                      58 lines  11-MAR-1993 21:51
--------------------------------------------------------------------------------
>     	The Maxtor 2190 (RD54) or the Priam 519 or Storage Dimensions
>     AT-160, all of which had the same geometry were pretty much the "max"
>     as far as large MFM drives went.  In some cases, there were "RLL"
>     variants of these drives, which would format to about 240 MB, but this
>     coding is not supported by the RQDX3.

  By the way, Storage Dimensions is/was owned by Maxtor and the AT160 *is*
a vanilla XT-2190.

>     	Sigma (and possibly others) did make a Q-bus controller that "talked
>     MSCP" on the Q-bus side and ST-506/RLL on the drive interface.  If you
>     could find one of these at a 'give-away' price, and wanted to live
>     dangerously, you could format an RD-54 RLL.  Internet news has had some
>     postings from folks who claim success with this trick, but it is risky.

  RD54's work fine in RLL mode, as do generic 2190's. We've had several dozen
of them in heavy use on file servers here in RLL mode for many years. The
only reason we're replacing them is that the spindle bearings are too noisy
to stand. [I've turned a number of XT-2190's into nice planters. I'll bring
some pictures to the Atlanta '93 Symposium to amuse you]

  RD53's / Micropolis 1325/1335 drives are problematic in RLL mode. In gen-
eral, 1325's will work and 1335's won't, but there are exceptions. I wouldn't
bet on it.

>     	If you want to try RD-53's or RD-54's, note that the E-store is showing 
>     B2-RD53-AA at $195, and B2-RD54-AA at $495.  These are refurbished, but
>     the usual deal with "B2" refurbs is that they carry a new product warranty 
>     -- typically "1 year return to DEC" for items in this class.

  Of course, you can get a new SCSI drive in the 170Mb range for $495 with-
out even trying hard. And larger drives are readily available. I'm paying
$848 for 520Mb 3.5" SCSI drives with a 5-year warranty. You still need the
controller, though. In a PC that's easy - most drives under 350Mb are avail-
able in IDE as well as SCSI (usually for a few dollars less).

>     	The RQDX3 logic supports a "maximum" MFM drive configuration of 16 data
>     heads and 2048 cylinders, with 17 sectors per track, which works out to
>     280+ MB in a single unit.  While some of the newer drives have this
>     many cylinders (in 2.5" format!), the maximum I've run across for an
>     MFM drive is 1314, in the Microscience 1090HH.  

  Most modern drives which report large numbers of cylinders are actually
operating in some translation mode (this is obviously untrue of ST-506 type
drives). The reason for this is that lots of older operating systems expect
17 (or some small number) of sectors/track, while the drive may have 90 or
more sectors/track. Thus the drive "lies" about the geometry in order to
present numbers the controller or host OS can accept.

>     The full capacity
>     of the drive (79.7 MB formatted) can be realized by loading the ZRQCH0
>     program, and before issuing "start" from the DR> prompt, entering console
>     ODT to patch the RD33 parameter table to the values correct for the
>     Microscience drive.  I've got two of them running happily with this
>     patch.

  Be careful with this - there are some subtle things related to bad block
replacement which can corrupt the disk.
================================================================================
Note 93.126       Low-end disk devices - The Digital difference       126 of 136
EISNER::WALLACE                                      66 lines  15-MAR-1993 22:41
                       -< ...Been looking for problems  >-
--------------------------------------------------------------------------------
    >  Be careful with this - there are some subtle things related to bad
    > block replacement which can corrupt the disk.
    
    	I have been wondering about this, since I had seen a couple of your
    internet postings -- one relating to "talking sweetly" to an RQDX3 to get
    it to format drives having geometries other than those in its standard
    library, and the other which _did_ mention the possibility of corruption
    when the "in service" bad-block replacement was initiated.  So far as I
    can tell there is no problem with bad block replacement during the initial
    low-level format -- and the second of the HH-1090's had 21 to be replaced,
    using up about 7 percent of the available RCT entries.
    
    	So far, I have not encountered any problems -- but this could be just 
    blind luck.  These are the "successes" all done on PDP-11's with the 
    ZRQCH0 formatter:
    
    	(1) Seagate ST-1100 (9 Heads/1074 Cylinders/3.5" MFM) formatted as a
    		"cut down" RD-54 to get full capacity.  Also can be run as
    	        an RD-53, at 71 MB, but this requires opening the interface
    		line to "Head Select 2**3" else some of the initial
    		twiddling done for the RD-53 will select heads the drive
    		doesn't have, making all concerned quite unhappy.
    
    	(2) One tired Seagate ST-251-1, which had lost Head 5; Cut down the
    		RD-32 table reflect the presence of 5 rather than 6 heads.
    		Drive formats fine to 5/6 standard capacity, and will pass
    		the soft error spec imposed by the ZRQE?? exerciser.
    
    	(3) Real DEC Q-540 RD-52, formatted to about 36 MB by patching the RD-52
    		table.  This one is not for the faint of heart.  So long as
    		any vestige of the original factory info is left, ZRQCH0
    		will very obstinately format the drive as a standard RD-52,
    		or will use less than you tell it of the available surface.
    		The "solution" is to lie to the formatter, telling it the
    		drive is really an RD-53.  The formatter will start
    		normally, writing sectors on every cylinder until it tries
    		to step beyond the last physical track on the disk.  It
    		then crashes with a hard error, as the head refuses to move
    		beyond its physical limits.  After this abuse, there is no
    		information remaining to confuse the issue, and the drive
    		can be formatted to the full 512 cylinders (less a few for
    		bad block replacement).
    
    	(4) Microscience HH-1090 runs either as a "stock" RD33 (the half-height
    		RD-53 replacement that never made it to market) at 71 MB or
    		an "enhanced RD-33" at approx 80 MB.
    
    	(5) Seagate ST-125 (20 MB 3.5" HH): This one is basically a "no
    		brainer" -- the drive has the same geometry as the RD-31,
    		and will format as such.
    
    	The only hint that something might be amiss from all of this has
    come from the ZRQG?? "summary" diagnostic.  This one is smart enough to
    realize that, notwithstanding what the media identification code says,
    if the geometry is not standard, then the drive is NOT an RDXX.  All of
    the other diagnostics (ZRQA??, ZRQE??) identify the drive according to 
    the media ID; ZRQG?? identifies the drive as "unknown", and while the
    LBN's for the replaced blocks appear to be listed correctly, the
    translation to cylinder/head/sector appear to be made on the basis of
    15 heads, 17 sectors per track, even though the actual geometry
    information _should_ be available by reading the disk itself.
    
    	So .. I'm waiting for the other shoe to drop.  I generally do NOT
    select handler initiated bad block replacement in my RT-11 system
    generations, however.
                                           -- Roger Wallace
================================================================================
Note 93.127       Low-end disk devices - The Digital difference       127 of 136
EISNER::WALLACE                                      50 lines  16-MAR-1993 21:30
                            -< RQDX3 BBR Problems? >-
--------------------------------------------------------------------------------
    	I was wondering if you could expand on the comment about the problems
    with data corruption which can occur with the RQDX3 when running with a
    drive of "non standard" geometry.  As noted in .126, I have not yet
    encountered any problems in RT-11/TSX systems using DU: handlers generated
    without handler-initiated bad block replacement.
    
    	The RQDX3 manual claims:
    
    > On hard disk drives, sectors with hard errors indicating that the sector
    > is defective are automatically replaced with available replacement 
    > blocks.  The total number of replacement blocks on a drive is specified
    > at format time and depends on the drive capacity.
      
    	This is certainly true at the time of low-level formatting.  The
    formatter lays down the tracks, scans for bad blocks and automatically
    replaces any found.  One could read the manual statements as implying
    dynamic bad-block replacement during system operation, but this is not
    what I have observed on the systems used here.  What _does_ happen is
    that when a read error cannot be recovered within a specified number of
    retries, the "forced error" flag for the sector involved will be set.
    Subsequent attempts to read the sector return an immediate hard error.
    Thus, during system operation, a bad block which develops will be
    flagged as "bad" but it is not actually replaced.  Such replacement
    _can_ be accomplished by running the "replace a single bad block"
    option of the ZRQCH0 formatter.  Often, if the failed read was a
    transient event, say a slight glitch in head motion because of abnormally
    low room temperature, "flagged" bad blocks of this type can be "recovered"
    simply by rewriting them.  After a bad block is found by DUP, simply
    use COPY/DEVICE/FILES DUn:/Start:xxx to write a "correct" single block 
    file into the offending sector.  If it really _was_ a transient problem,
    this may well be the end of it.  If the drive is dying, you will find
    yourself repeating the exercise far too often. 
    
    	Sometimes, a "slightly tired" MFM drive can be accommodated by
    changing the retry limit in the handler.  It is interesting to note the
    wide range of opinion about how many retries should be allowed --
    Chester Wilson's DUCM handler(s) allow three by default; Seagate specs
    the error rate for their modest MFM drives based on a successful read
    within 16 (!) retries.
    
    	Clearly, if the _system_ initiates bad block replacement based on a
    drive geometry deduced from the media ID code, and the drive actually
    has a different geometry, there are likely to be problems.  Also, it
    does happen that certain drive geometries and bad block combinations
    cause the ZRQC?? formatter to fail where others (e.g. Webster's "WOMBAT")
    succeed.  My work-around in the latter case has usually been to
    slightly increase the number of replacement cylinders and
    correspondingly reduce the total LBN size and try again.
    
                                                       Roger Wallace
================================================================================
Note 93.128       Low-end disk devices - The Digital difference       128 of 136
EISNER::KENNEDY "Terry Kennedy"                      21 lines  17-MAR-1993 02:20
                      -< Generally problems in host code >-
--------------------------------------------------------------------------------
>    	I was wondering if you could expand on the comment about the problems
>    with data corruption which can occur with the RQDX3 when running with a
>    drive of "non standard" geometry.  As noted in .126, I have not yet
>    encountered any problems in RT-11/TSX systems using DU: handlers generated
>    without handler-initiated bad block replacement.
    
  If you don't have BBR configured in your handler, you'll be safe as you
will never do a complete BBR (outside of the ZRQC formatter, of course).
However, I believe RT-11 is the only OS which gives you this level of con-
trol - all of the others do BBR.

  There are two main classes of BBR - controller-initiated and host-initiated.
Various controllers need different levels of host support, with the Q-bus
backplane controllers needing the most.

  What this boils down to is that the host code may have some underlying
assumptions about the disk based on the returned model code which may not
be true for the disk you're using. Also, I've seen things like assumptions
that there are always at least X RBN's available, etc.

  I'll post more on this if you're interested...
================================================================================
Note 93.129       Low-end disk devices - The Digital difference       129 of 136
EISNER::WALLACE                                      32 lines  26-MAR-1993 20:42
                -< Thanks for Info.  I'll Breathe more Easily! >-
--------------------------------------------------------------------------------
    	Thanks for the info -- I'll rest a bit easier.  I had thought that
    the controller _should_ be aware of the disk geometry, since it accepted
    the geometry information as input from the format program and wrote it
    to the disk.  OTOH, the _system_ might be reading tables from somewhere
    which could lead to some unpleasant surprises.
    
    	At the time it was introduced, DEC's technical literature made a
    point of saying that the RQDX3 could support new drives without
    firmware revisions because the drive geometry was written to the disk
    at format time, rather than being stored in controller firmware --
    which _was_ the case for the RQDX1 and RQDX2.  However, from DEC's
    perspective, "support" for a drive under a particular operating system
    has always covered more than just getting it to run -- diagnostics and
    utilities also had to be able to deal with it.  For quite a while the
    RA-82 (I think) was in the category "Not supported, works fine" for the
    small PDP11's.  If you had some way of getting it formatted, and had a
    "large DU" handler, it would run, but the distributed (RT-11/XXDP) 
    formatter, handlers, and utilities did not know how to deal with the full 
    capacity of the drive.
    
    	As far as the ZRQC?? patches are concerned, a couple of cautions
    must be observed.  Folklore has it that you must keep the media ID code
    set equal to one of the "known" drives.  Also, I have usually either
    left the RBNs unchanged from the value associated with the media ID
    _or_ increased them somewhat.  Whatever set of parameters is specified
    for the drive must be self-consistent -- the total of LBNs, XBNs, DBNs,
    and RBNs had better be less than the absolute number of physical sectors
    on the formatted drive.
    
                                                   Roger Wallace
    
                                              
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Note 93.130       Low-end disk devices - The Digital difference       130 of 136
EISNER::LAFERRIERE "James W Laferriere"               9 lines  15-MAY-1993 18:18
                         -< What is it?  NEC CDR25BJ. >-
--------------------------------------------------------------------------------
	ok gents/ladies this is my first question here about low end disks

		I've seen what seems to be a scsi cd-rom drive at one of my
		local stores.    an  NEC CDR25BJ.    MY question is 

			IS IT ?   the counter person was totally ignorant of the
				drives possibilities.

				Thanks Jim Laferriere
================================================================================
Note 93.131       Low-end disk devices - The Digital difference       131 of 136
EISNER::STRIEGEL "Alan Striegel"                     11 lines  17-MAY-1993 15:43
                            -< NEC CDR-25 is SCSI >-
--------------------------------------------------------------------------------
>I've seen what seems to be a scsi cd-rom drive at one of my local stores.   
>an NEC CDR25BJ.    MY question is 
>
>IS IT ?   the counter person was totally ignorant of the drives possibilities.

     There is a model from NEC Technologies known as the Intersect CDR-25.

     According to my sources, this appears to be a SCSI CD-ROM drive in the
portable form-factor (i.e. external) with a 650 msec access time.  Price range
is $200-$300 including 2-yr warranty. 

================================================================================
Note 93.132       Low-end disk devices - The Digital difference       132 of 136
EISNER::LAFERRIERE "James W Laferriere"              21 lines  25-MAY-1993 22:20
                       -< another SCSI  CDROM  FROM NEC >-
--------------------------------------------------------------------------------
>             <<< Note 93.131 by EISNER::STRIEGEL "Alan Striegel" >>>
>                            -< NEC CDR-25 is SCSI >-
>
>>I've seen what seems to be a scsi cd-rom drive at one of my local stores.   
>>an NEC CDR25BJ.    MY question is 
>>
>>IS IT ?   the counter person was totally ignorant of the drives possibilities.
>
>     There is a model from NEC Technologies known as the Intersect CDR-25.
>
>     According to my sources, this appears to be a SCSI CD-ROM drive in the
>portable form-factor (i.e. external) with a 650 msec access time.  Price range
>is $200-$300 including 2-yr warranty. 

		Also for your info, I just recently foud this out

		N.E.C.	CDR-36 is also SCSI
			380 m.s. access
			64k cache

		Or so I was told by the sales man here ( under 200 )
================================================================================
Note 93.133       Low-end disk devices - The Digital difference       133 of 136
EISNER::LEDERMAN "Bart Z. Lederman"                   8 lines  26-MAY-1993 07:30
                            -< Older model of NEC >-
--------------------------------------------------------------------------------
    I have an NEC CDR-36 on my Mac.  It is SCSI.  It's also an older model
    (it's been superceeded by the CDR-37 and CDR-25), but as long as you
    don't need the fastest possible drive, and don't need multi-session
    Photo CD, it works fine.
    
    Most of NEC's models are available with SCSI interfaces, though some
    are also available with PC interfaces (including the CDR-36, so watch
    which model you actually buy).
================================================================================
Note 93.134       Low-end disk devices - The Digital difference       134 of 136
EISNER::KRULEWICZ                                    14 lines   5-JUN-1993 16:48
--------------------------------------------------------------------------------
Ok, Ok, years ago I got a PC type TEAC FD-55GFR-142-U 5.25" floppy and by
setting the jumpers to FG, UO, U1, D0, DC, and, I, it turned into a DEC RX33
when connected to an RQDX3.

Well, now it's time for the TEAC to go back to being a PC Floppy, however,
I don't know where I recorded the original jumper settings and it won't
work like this.

Help anyone?

- Jerry

PS - Is this what they mean by "reverse engineering?"

================================================================================
Note 93.135       Low-end disk devices - The Digital difference       135 of 136
EISNER::BROWN "Rob Brown -- Who_am_I #483"           18 lines  14-AUG-1993 00:30
                              -< Seagate ST-4053 >-
--------------------------------------------------------------------------------
    
    I have salvaged a Seagate ST-4053 from my PC and want to install it in
    a VS2000.  I know that I need to change the jumper to Drive Select 3,
    but I am not able to identify the correct position.
    
    When I turn the drive upside down (circuit board up), with the
    connectors towards me, there is a row of eight jumper positions in
    between the two connectors.  (The circuit board is labeled "ST-4096
    controller" interestingly enough.)  When the drive was removed from the
    PC, there was a jumper installed in the second position from the right. 
    
    Should I move this jumper?  To which position?  Anything else I need to
    do?
    
    Thanks for the help.
    
    -Rob
    
================================================================================
Note 93.136       Low-end disk devices - The Digital difference       136 of 136
EISNER::KENNEDY "Terry Kennedy"                      14 lines  14-AUG-1993 03:11
                   -< Not a particularly good drive, hints >-
--------------------------------------------------------------------------------
>     I have salvaged a Seagate ST-4053 from my PC and want to install it in
>     a VS2000.  I know that I need to change the jumper to Drive Select 3,
>     but I am not able to identify the correct position.

  These drives (ST-4096 family) are not exactly the greatest (and weren't
even when they were new). 80% DOA rates were not uncommon at distributors.

>     Should I move this jumper?  To which position?  Anything else I need to
>     do?

  PC's (AT and up) generally run the hard disk at the second possible select
(DS1 if you start at 0, DS2 if you start at 1) while VAXen generally want the
first hard disk at the third position (DS2 if you start at 0, DS3 if you start
at 1). That's about as far as I can generalize for the ST-4096, though.
