Microbotics M1230XA accelerator board repair

[roMancer]

Hi!
I have an old Microbotics / Paravision M1230XA accelerator board, and it's not working properly.
Can you help me debugging it?

For starters, a few screenshots would help: SetXA utility window / running, Early Startup Menu boards listing, "showconfig" output, SysInfo screen with speed test results (each of course with a working M1230XA installed).

I mostly test my board with Kickstart 3.0 - are you aware of any issues regarding KS3.0 and the M1230XA?
(apart from the fact that RAM has to be added "manually" / software-wise)  

Thanks!

[roMancer]

hi everyone,
thanks for your replies :-)

yes, I've already done a couple of things:
- M1230XA disk installed, setup utility, etc.
- reseated and tested five different RAM SIMMs
- replaced all capacitors on the board with new ones
- replaced battery with a new one
- tested in both kickstart 3.0 and 3.1 Amiga 1200s

my M1230XA has a 68RC030@50mhz, no FPU, no RAM
SetXA utility is set to these specs/values.

this is the situation:
- clock works (with a new battery)
- SetXA works: board recognized, "test" jumper recognized
- SetXA says: Hardware version: 0
- eeprom works: SetXA settings remembered
- processor (w. MMU) recognized by "showconfig" and SysInfo
- SysInfo shows 68030, MMU. speed results: ~1.5 times speed of a stock A1200 (~1800 dhrystones)
- board not listed under "Boards" in Early Startup, and not listed by "showconfig"
- so far: same situation on both ks3.0 and ks3.1

now when i install some RAM:
- under ks3.0 "AddXAMem" (or SetXA "Add memory") crashes the machine. new memory shows up for a second in WB title bar, then both chip- and fast-mem go to zero, then machine becomes unusably slow and has some screen corruption.
- under ks3.1 machine does not boot (power-led, keyboard led blinks, no floppy click, black screen)

the speed increase when installing the board is very little (see above).
(note the results at http://amiga.resource.cx/perf/aibb.html : m1230xa without RAM listed with about 4-5 times the speed of a stock A1200)
but I've tested with a (proved working) Blizzard1230 (FPU, no RAM, no maprom), and the results are about the same (~1.5 times A1200 speed), so the missing RAM might slow down the m1230xa (drastically).

currently, I'm drawing this conclusion:
the board works fine, except for anything RAM-related.

still I'd like to see some screenshots from a working M1230XA without RAM installed:
- does it show up in early startup menu -> boards? (kickstart 3.1 only?)
- does it show up in showconfig?
- is SetXA's "Hardware version: 0" info correct?
- what are SysInfos speed results?

...just to confirm what I see with my board.

I dont know how AutoConfigging works, if it's the same process that gets triggered by "AddXAMem" (or "SetXA add memory"), if the board MUST show up regardless of some AutoConfig function is has or hasn't, etc. - but we'll find out when we get there... ;-)

[roMancer]

...you've already tried it with different sticks of ram, and attempting to run the ram config utility (or autoconfig the ram under 3.1) is causing it to crash, correct?

yes, correct.

If you've already triple-checked that any jumpers are in the right positions

yes. the manual says nothing about jumpers and no FPU installed, so I'm assuming FPU-clock jumper is irrelevant in my case. the test jumper should be more or less irrelevant anyway.

and that everything  is clean, I'd suspect the ram socket might be faulty.

hm. it looks flawless to the naked eye. do you think it's worth checking with a multimeter? (now a schematic would come in handy...)

[roMancer]

hm, the simm socket seems to be fine. checked all contacts to the points where they're soldered to the pcb, and then again from there to the other side of the pcb.

[roMancer]

note to self:
Jerry M. Robinson. found his name in some newsgroup. he designed and coded the M(BX)1230XA.

https://groups.google.com/forum/#!topic/comp.sys.amiga.hardware/ARRc3D74GC0

anyone know Mr. Robinson?

[roMancer]

some late feedback, just for completeness' sake:
problem solved - it works again! :-)
MBRTest-2 (memory testing software from M1230XA disk) reported errors - it turned out to be some broken address- or data line. adding a wire fixed the problem.
thanks a lot for your support!

(updated blog article: https://amigaalive.blogspot.com/2017/05/help-microbotics-paravision-m1230xa.html )