Intel MDS Series II IOC question

[George L. Rachor Jr.]

Greetings Dave,


Possibly helpful hints from a friend not on this list:
------------
Subject: Re: Intel MDS Series II IOC question (fwd)

Hi George,

My first thought is SCANBE.
My second thought is SCANBE.
My third thought is... can you guess?
Replacing the SCANBE sockets with AUGAT barrel type on the older IOC's
has always solved my 5 beep test problems.  Making sure all socketed 
components
are properly seated in reliable sockets.  The manuals, flow charts, etc...
all say to replace the IOC if the 5 beeps test fails.  The manual called:
Customer Engineer Diagnostic System Test Operating Instructions For 
Series II Systems
(121619-001)  may break down the 5 beep test, but I do not have a copy.

Tips for replacing the SCANBE sockets.
1. Pull the plastic housing of the SCANBE socket off the board.
2. Remove the mylar sheet from between the pins.
3. On the component side grab one of the pins with needle nose pliers
     while heating same pin on the solder side, pull to remove.
      Repeat for all pins.
4. Use solder wick to remove solder from holes and clean up.
5. Clean area with flux-off if needed.
6. Install AUGAT machine barrel socket.
7. Clean area with flux-off.

Randy


=========================================================
George L. Rachor Jr.		george at rachors.com
Hillsboro, Oregon               http://rachors.com
United States of America        Amateur Radio : KD7DCX

On Thu, 1 Sep 2005, Dave Mabry wrote:

> I think there are some Intel MDS owners here, and even some who use them!  ;) 
> Maybe one of you will know this detail.
>
> I'm trying to troubleshoot a problem on one I just got, a Series II, model 
> 225.  There is a large PC board on the back panel of these beasts called an 
> IOC (Input/Output Controller).  It contains an 8080 cpu, some ram, some rom, 
> and basically all the I/O for the machine on the back panel.  It is commanded 
> by the system's cpu (a different board plugged into the front multibus 
> chassis) through a couple of I/O ports, if I remember correctly.
>
> The IOC board has a three-position switch on the back.  One position is 
> "line" and in that position it is connected to the system cpu and does its 
> everyday work of controlling the I/O for the MDS.  One position is "local" 
> and in that position I think all it does is echo characters typed on the 
> keyboard to the crt.  The third position, "diagnostic" causes it to run some 
> internal confidence test.  In that position, if everything is healthy, there 
> are a series of two beeps, a pause, then three beeps after reset.  After that 
> there are some choices on the crt that let you run a few different tests from 
> the keyboard.
>
> The one I'm working on will beep twice, then pause, then only one beep. 
> Nothing further happens.  No characters on the crt (which does have a raster, 
> so at least part of the crt-controller function of the IOC is working), no 
> apparent response to keyboard typeins.
>
> My question is this...does anyone know what part of the diagnostic is failing 
> when there are only three beeps instead of five?  The documentation I have 
> only says it should beep five times but doesn't say what each beep signifies. 
> It would help narrow down my search for the problem if I know what part of 
> the test is failing.
>
> I'd love a disassembly of the firmware of that board, but I've never seen it 
> or any source for it.  That would be very helpful.  Anyone have such a thing? 
> I don't remember ever seeing anything like that from Intel, but it was a long 
> time ago and I may have just forgotten.
>
> I'll be diving into this problem this weekend, but if anyone can help with 
> the above couple of questions that would be wonderful.
>
> Thanks in advance!
> Dave Mabry
>
>
>