VOGONS

Search

Common searches

IBM PS/2 P70 "110 ?????" Error. ? Memory problem

Topic actions

First post, by polishvito

Posted on 
User metadata
Rank Newbie
Rank
Newbie

I'm working on a PS/2 P70 that I recently got. Hard drive was DOA which limited my ability to do much with it, confined to use programs off the floppy drive. Until I got the MCIDE and was able to boot off a CF card. I have DOS 6.22 on the card with various programs.

The problem that I am now running into is the system will randomly hault, and display:

110
?????

To the best of my research, the 110 error code is documented as planar parity error. I don't have any RAM expansion cards in this machine. It has four 2mb 72pin SIMMs.

I have run both the diagnostics on the IBM reference disk, as well as CheckIt (the long comprehensive memory test) and the memory keeps checking out. Something is obviously still wrong. Does anyone have any ideas about how I could go about figuring out where the problem is? I suppose I could remove all the RAM chips but one and keep swapping in and out until I find one that is bad. This is just a tough system to work on while it is disassembled given its Luggable form factor.

https://www.scribd.com/doc/96081065/Code-Errors-IBM - this is a copy of the IBM documentation explaining the error codes.
"110
(Planar parity.)"

"1. Go to
Memory Checkout
2. DIMM card.
3. Detach the expansion unit if it is attached to the computer.
4. System board."

If anyone knows what that is referring to I'd be happy to hear about it.

Oh and I already took the SIMMs out, cleaned them, compressed air to the sockets, put deoxit on the pins and put them back in the machine. Not that I would expect the tests to have completed if contact was an issue.

Reply 1 of 7, by Horun

Posted on 
User metadata
Rank l33t++
Rank
l33t++

Reading about the ram I saw it must use 2MB 85ns Parity SIMMs with Presence Detection. If using any other type and speed (according to below) you will get an error.
https://ardent-tool.com/memory/Identification.html#SIMM_PD ... and it tells how to check the PD.

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 2 of 7, by polishvito

Posted on 
User metadata
Rank Newbie
Rank
Newbie
Horun wrote on 2023-08-26, 23:23:

Reading about the ram I saw it must use 2MB 85ns Parity SIMMs with Presence Detection. If using any other type and speed (according to below) you will get an error.
https://ardent-tool.com/memory/Identification.html#SIMM_PD ... and it tells how to check the PD.

I’ll take a look when I open the machine next to verify exactly what type they are. I really didn’t pay much attention since I had the computer booting and everything had seemed to work at that time.

Reply 3 of 7, by Horun

Posted on 
User metadata
Rank l33t++
Rank
l33t++

Did you also pull the planar board and clean all it's contacts ? https://ardent-tool.com/8573/P70_Project.html
Which exact Planar does your have ?

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 4 of 7, by polishvito

Posted on 
User metadata
Rank Newbie
Rank
Newbie
Horun wrote on 2023-08-27, 02:34:

Did you also pull the planar board and clean all it's contacts ? https://ardent-tool.com/8573/P70_Project.html
Which exact Planar does your have ?

It’s the 8573-061 with the 20Mhz 386Dx.

And no I hadn’t taken the entire planar out

Reply 5 of 7, by Horun

Posted on 
User metadata
Rank l33t++
Rank
l33t++

Thanks. I would thoroughly check your ram type first before pulling out the planar.

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 6 of 7, by polishvito

Posted on 
User metadata
Rank Newbie
Rank
Newbie
Horun wrote on 2023-08-27, 12:20:

Thanks. I would thoroughly check your ram type first before pulling out the planar.

That’s what I plan on doing.

I’ve finally found something consistent with this - tried a memory test program called Gold Memory V4.42 and it consistently crashes at the same point in the ram test at 15%. It doesn’t give me a diagnostic report unfortionately or tell me much more info, but I can pull out sticks and see if the problem is the same.

Will be out of town for a few days, so will post my results probably next week.

Reply 7 of 7, by polishvito

Posted on 
User metadata
Rank Newbie
Rank
Newbie

Okay so the results are in. And.... I am a dumb ass.

A really big dumb ass. So much so that I don't even really want to post about it but I figure I owe to anyone in the future who is looking at similar issues.

I open it up and start taking out the ram sticks. My plan was to reinsert one at a time and run through all the checks, though I had been suspecting Bank 0 since some of my tests would crash early on.

By the time I get down to Bank 3 - I see that one of the clips wasn't engaged. I had taken out the sticks when I did my initial cleaning to clean them and put them back. It must have been in just enough that it was passing some of the memory tests but not enough. Since I had everything out already I proceeded with my plan of one stick at a time and testing, while making sure they're actually in the socket. All the ram now seems to work, all the tests pass, and the machine has yet to crash on me with that error.

Probably should have checked that earlier on instead of wasting a bunch of time with diagnostic programs. Whoops.

Go to top of page Go to top of page
Back to General Old Hardware
Close window
Close window