MicroVAX II - TK50 problem

[willisjo at zianet.com]

Adrian Graham writes: 

> the uVAX II has a Q22/Q22 backplane so the positioning of the TQK50 is
> important, as is the RQDX(2/3) disk controller which should be last on the
> bus. The first 3 slots are CD types and are reserved for CPU/Memory, the
> rest (I can't remember which size cab you've got) are serpentine so if
> you've only got the CPU, 2 mem boards and the disk/tape controllers then the
> TQK50 should be on top of the RQDX3.
> I notice 8 TX lines which means there's a quad-height DHV11 there, probably
> next to the memory. If you've got a DEQNA ethernet half-height board as well
> then that'll mean you have TQK50/DEQNA occupying a quad-height slot and the
> RQDX3 on its own in the AB side of the slot next to that. 
> 
> Google for 'vax q22/q22 backplane' and you'll find an excellent explanation
> of how the uvax backplane works. 
> 
> cheers 
> 
> a/w 
> 
 

I did know about the serpentine weirdness. It caused me a great deal of 
grief in getting the system to pass its self tests in the beginning, before
I stumbled (quite accidentally) across hamster's digital$resources
page on Qbus. However, I think you may have hit on something. The RQDX3 is
not at the end of the bus. If memory serves (I'll verify this
after I get home from work today), the backplane arrangement is something
like this:
     A        B        C        D
+-------------------------------------+
|                CPU                  |
+-------------------------------------+
|                Memory               |
+-------------------------------------+
|     TQK50*       |                  |
+-------------------------------------+
|     M9047        |                  |
+-------------------------------------+
|     RQDX3*       |                  |
+-------------------------------------+
|                DHV11                |
+-------------------------------------+
|                ???? **              |
+-------------------------------------+
|                  |                  |
+-------------------------------------+
|                  |                  |
+-------------------------------------+ 

 

*  I may have these swapped, OR I may have the M9047 swapped
  with the TQK50
** This is another board. I believe a general-purpose DMA
  interface. I'll check when I get home today. 

Another note, here's some more strange behavior from VMS, which
I now believe may also be linked to a QBus misconfiguration: 

$ SET TERMINAL TXA0:/PERMANENT/INTERACTIVE/DEVICE_TYPE=vt100
%SET-W-NOTSET, error modifying TXA0:
 -SYSTEM-F-TIMEOUT, device timeout 

Here's the info on TXA0: 

$ SHOW TERMINAL TXA0:
Terminal: _TXA0:      Device_Type: VT100         Owner: No Owner 

  Input:   9600      LFfill:  0      Width:  80      Parity: None
  Output:  9600      CRfill:  0      Page:   24 

Terminal Characteristics:
  Interactive        Echo               Type_ahead         No Escape
  No Hostsync        TTsync             Lowercase          Tab
  Wrap               Scope              No Remote          Eightbit
  Broadcast          No Readsync        No Form            Fulldup
  No Modem           No Local_echo      Autobaud           No Hangup
  No Brdcstmbx       DMA                No Altypeahd       Set_speed
  Line Editing       Overstrike editing No Fallback        No Dialup
  No Secure server   No Disconnect      No Pasthru         No Syspassword
  No SIXEL Graphics  No Soft Characters No Printer Port    Numeric Keypad
  ANSI_CRT           No Regis           No Block_mode      Advanced_video
  No Edit_mode       DEC_CRT            No DEC_CRT2        No DEC_CRT3 

Thanks
John Willis