NCR 286 gives 5 beep code

[oblivion]

I recently picked up an NCR 286. It's virtually identical to the one in this VWestlife video

The only difference is mine has a header for an external battery and the case badge is different. Unfortunately when mine powers on I get 5 short beeps and then nothing. I tried looking up the code but it looks like it uses an NCR BIOS so I didn't find any chart for my particular machine. I tried removing the dead lithium battery and installing an external battery, tried replacing the CPU with a known good working 286/12, and tried different discrete ISA VGA cards but same error. There is a switch box and a few jumpers on the board but everything looks set as it's supposed to be (there is a jumper/switch guide on a sticker under the cover). I played around with the jumpers and switches anyways just to be sure but no difference. At this point, I'm wondering if maybe the 1MB soldered on RAM or some other chip is bad. any suggestion?

 

[modem7]

any suggestion?

Do you have the ability to program/burn a set of Supersoft/Landmark Diagnostic ROM's for the motherboard ?
You would use the AT version of those.

More information at [here]. The target of that web page (and children pages) is the IBM 51xx series of computers, but the AT version of the diagnostic ROM's is fine for any compatible AT clone. Note the special video card requirements.

 

[oblivion]

Do you have the ability to program/burn a set of Supersoft/Landmark Diagnostic ROM's for the motherboard ?
You would use the AT version of those.

More information at [here]. The target of that web page (and children pages) is the IBM 51xx series of computers, but the AT version of the diagnostic ROM's is fine for any compatible AT clone. Note the special video card requirements.

View attachment 1256692

Unfortunately, I do not. I did do a quick look on eBay and found someone in Poland selling a pre-flashed ROM but it looks like it's the one for XT class machines.

 

[modem7]

Unfortunately, I do not. I did do a quick look on eBay and found someone in Poland selling a pre-flashed ROM but it looks like it's the one for XT class machines.

Maybe you could put a request in the 'Vintage Computer Items Wanted' section here at the VCFF, or use the list at [here].

A reminder of the special video card requirements. If you don't have a suitable video card, you will be relying on the beeps issued by the diagnostics.

 

[oblivion]

Maybe you could put a request in the 'Vintage Computer Items Wanted' section here at the VCFF, or use the list at [here].

A reminder of the special video card requirements. If you don't have a suitable video card, you will be relying on the beeps issued by the diagnostics.

Thanks for making me aware of this diagnostic ROM, I'll ask around as you suggested and hopefully, I can get ahold of one. may come in handy in the future as well.

I do have an IBM CGA card so hopefully that will work with the ROM.

One more question, there seem to be two ROMs a "high" and "low" ROM, do you know which one the diagnostic ROM will replace?

 

[bolex]

This NCR manual indicates 5 beeps is a "Fatal Error". That's helpful.

 

[modem7]

One more question, there seem to be two ROMs a "high" and "low" ROM, do you know which one the diagnostic ROM will replace?

The AT version of the Supersoft/Landmark Diagnostic ROM is a set of two 32KB sized ROM's (although, if required, a single 64 KB ROM was available).
At the web page that I pointed to, there are two 'AT' (5170) binary files for download, and they map to HIGH/LOW per the following:

5170_ODD_U47_27256.bin --> HIGH
5170_EVEN_U27_27256.bin --> LOW

I do have an IBM CGA card so hopefully that will work with the ROM.

That should be no problem at all.

 

[oblivion]

Well, I received the diagnostic ROMs and I'm happy to report they seem to work.

looks like it fails at "protected mode CPU". the manual suggests swapping out the CPU if this happens. I tried this again with a known good CPU and I got the same error. I tried cleaning the connectors and socket as well as visually inspecting it for anything obvious but the same issue. I'm wondering if the socket itself is just bad. I also get 2 beep errors here 6 hi/low 1 short and 6 hi/lo 2 short. The first one indicated "monitor not initialized" according to the manual and the second error isn't even listed.

 

[modem7]

looks like it fails at "protected mode CPU". the manual suggests swapping out the CPU if this happens. I tried this again with a known good CPU and I got the same error. I tried cleaning the connectors and socket as well as visually inspecting it for anything obvious but the same issue. I'm wondering if the socket itself is just bad.

I seem to recall that someone here had a protected mode error (displayed on-screen I think), and the cause was a bad CPU socket.

In the IBM 5162 and IBM 5170 (IBM AT), we have also seen that test fail when the diagnostic is unable to completely switch back to real mode from protected mode. In those cases, it was the MC146818 chip that was faulty. (One byte of RAM in the MC146818 is used to store the shutdown status/reason).

I also get 2 beep errors here 6 hi/low 1 short and 6 hi/lo 2 short. The first one indicated "monitor not initialized" according to the manual ...

Per [here], the speaker beeping to indicate "Cannot initialize monitor" is a known behavior. That appears to be a bug in the diagnostic. It even happens on my fully functional IBM 5170 motherboard. Ignore it.

... and the second error isn't even listed.

The beeps are for people who can't get a visual display of the diagnostic output. I suggest that you ignore the beeps.