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Problems with IBM clone

D

dengelland

Member
Joined
Dec 19, 2008
Messages
47
I'll try to keep this simple (thats the kind of mind I have).

At work we have a Haake Buchler Reohmeter controlled by a vintage pc.

It had not been used for 15 yrs. so I uncovered it 7 cleaned it up and started running some tests with it.
The manual describes the pc as having a 80286 microproccessor
640 K Ram
1 - 1.2 mg floppy 5.25 disk drive
1 - 20 mg hard drive
80287 coprocessor
moniter, printer & keyboard
8 expansion slots
Faraday A-tease motherboard
AT form
Anyway it worked just fine till I changed the clock batteries because I got tired of setting the clock everytime it was booted up.
Also the fresh out of school chemical engineer working in R&D decided maybe it wasn't such a bad thing at that and started running some tests.
When I got back to work after my long break, the pc wouldn"t boot up and gave no errors. We got it going again by unhooking the power to the hard drive, trying to boot, then hooking power back up and it booted. We decided not to shut it downtill we could get it fixed.
Then after being off for a weekend, when I came in, it was off & when I turned it on it checks the 640 ram, starts checking ram over 1 mg then displays (illegal shut down code in cmos) and then loops back.


The motherboard is a Faraday, A-tease with a date on some chips of 1985 and that is about the age of the machine.
I have tried every suggestion that I have been able to track down on the internet to get to the bios to clear the error ( from F1 to disconnecting the keyboard to trying to reset the bios back to default) all to no availe.

Now what I think what happened is that the clock batteries had been laying in there for 15 yrs and leaked down onto some chips and corroded them.

Do you guys think this is saveable or should i just look for another motherboard and if so, what should I look for?I have seen some on the internet, but am not smart enough in that area to know whether they would fit.
There is a whole machine on e-bay but they want ore than I lost in my 401K the last 3 months.
This machine is no longer made and new versions cost more than I make in 2 yrs.
Any help you could give me would be greatly appreciated.

Thank You

David
 
Clock batteries

Clock batteries

Sounds like there might be something corrupted in the CMOS. Have you tried removing the clock batteries to see if the CMOS discharges ? If not, try that and the next time you boot it, try it without the batteries.
patscc
 
IBM clone trouble

IBM clone trouble

Yes, I presently do not have the batteries in it. I can do without clock if necc.
 
Hd

Hd

When you disconnected the power to the hd, did you disconnect the actual interface cable as well ? If not, do so ( and the power ) and try booting. Post what happens.
patscc
 
clone problems

clone problems

I disconnected power and other cables, got (illegal shutdown code in cmos) with them dissconnected and again with them connected.
 
IBM clone cmos problems

IBM clone cmos problems

IBM clone mobo 80286.jpg


Couple of pictures of equipment and 1 of Mobo found on ebay, any comments as to whether it may work? Should a mobo like this have bios already in cmos that might work in my system?

Thank You


View attachment 1079

View attachment 1080
 
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Did you actually *see* corrosion on the motherboard?

Where are you? Maybe there's someone local who could help you out? First thing I'd do is run some diagnostic tests, but you need a floppy disk for that and I'm going to assume that you don't have another machine that could copy a file off the internet to a 5 1/4" disk?
A lot of hassle getting another board and installing it if all you really need is just to reset the CMOS memory (which you have to do in any case). You did put a battery back in, didn't you?

I wouldn't give up on that board too quickly, but even if you get a replacement you might still need 5 1/4 capability anyway to set things up. Any 286 board would probably work as long as it's fast enough and isn't physically too big, and uses the same co-processor.

Neat-lookin' piece of equipment; hope ya get it working!
 
If it's helpful, I have the schematics for the A-Tease.

When I owned one, my own experience was that the sockets on the board were terrible. I was continually reseating chps to get the thing to work. When it worked, it was a nice AT clone for the time.
 
Problems with IBM clone

[/INDENT]We deal with PVC plastic.

Yes I've replaced battery.

Machine is in Benton, KY. western part of state.

I can see where the batteries have leaked onto the chips.
Cleaned it off gently with toothbrush and air pressure.

Beings I am a vintage (65 yr. old) novice could you help me
identify the memory chip on the board. I read that if a chip is
removed then pc started it will tell how to reach bios.
Tried removing memory card from slot & starting but still
got the same thing.

I did find Faraday jumper settings and lay out on internet, will see if
that helps tonight

Working 5p to 5a next 2 nights


Thanks for replies & help
 
I do not believe (at least it wasn't the case in mine) that there is a setup program in the BIOS (unless someone has changed it). The A Tease is basically an IBM 5170 (right down to the 6 MHz 80286) clone with onboard serial and parallel ports; there's nothing special about the chipset.

An IBM 5170 (PC AT) setup disk should work with this system.
 
IBM clone

IBM clone

I found a partial manual for my faraday board at Dell-UK, it shows a partial layout and the jumper & switch settings. It shows a JL3 4 as jumped for maintenance. any clues as to what this does?
 
Usually, if you repeated hit a key on the keyboard while the computer is booting up, it will generate an error and allow you to continue or enter the CMOS (if it has one).

If not, it uses a floppy based setup program and I can send you one that will work on, just about anything.

Seems stange that the battery should suddenly cause a problem after being in there for 15 years.

If a replacement becomes necessary, two things. First, if you're going to buy off on FeeBay, make sure you, at least, see a picture of the actual board you're going to get working. Second, you can replace a full-sized AT board with a smaller AT form factor, but, not the other way around.

You might want to upgrade the board to something like a 486DX as long as you have to change it to get more speed out of the aplication. I doubt there is anything special about the software so that it HAS to run on a 286 with FPU. A 486DX has an internal FPU and is in the x86 class and can take much more memory.

I have good working, tested motherboards in all the x86 classes.
 
This jumper is the same as the corresponding undocumented (mostly) one on the IBM 5170--it's connected to PI5 on the 8742 keyboard controller and is installed when the motherboards are undergoing testing during manufacturing.

Leave the jumper off--you can't use it without a special jig to pick up the codes output by the diagnostics.

The board's probably not going to boot correctly until a battery is installed.

Regardless, if you decide to get another motheroboard (Druid may have the right idea, but there are some CPU-speed sensitive applications, so be careful--your Faraday is only a 6MHz system), bear in mind that you may need to have the 2 serial ports + parallel port on the board, or you'll need to install a multi-I/O card to support this.
 
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A picture is worth a thousand words.
This is what I am trying to get past.
The machine wasn"t used for 15 yrs. but still worked when first started for about 2 months but had to set clock every time booted, that is when batteries were changed and corrosion found. Now we get this and it just loops round & round, with batteries or without.
I think I need to clear error but don"t know how.

illegal code on Haake 001.jpg
 
Is the MC146818 at U148 in a socket? Check to see that it's seated if it is.

Here's what's going on with that message:


  • The processor tests the lower 640K of RAM (which shows on your display).
  • Next, the CPU is switched into protected mode to test the memory above 1MB.
  • The CPU needs to be switched back to real mode. Since there's no (documented) way to do this, a code is written into a location in CMOS and the keyboard controller is instructed to reset the CPU.
  • The CPU comes back from a reset, notices that the reset was the result of a "shutdown" and checks the reason why--that byte that was written in CMOS.
  • The byte the BIOS reads does not match one of the permissible values and the BIOS gives the error and halts with your message since it can't figure out how it got where it is.
I'm guessing that the CMOS Clock chip is either seated badly in a socket or is toast. If it's in a socket, you're in luck--you can replace the chip with one of the CMOS-with-lithium battery built-in chips and forget about the battery altogether. Much cheaper than another motherboard.
 
The MC146818 at U148 is soldered in.
It happens to be 1 of 2 that got corrosion on them. The other is next to it in U127 also soldered it.

Do I have any choices now?
Another board or unsolder & resolder in a new chip?


I really, really want to thank you.

David
 
It depends on your soldering skills.

If it were me, I'd put a socket in place of U148, clean the chip really well (sometimes corrosion can get to the underside of the IC, raising all sorts of issues), plug the chip in and see if it works. If not, I'd replace the chip with a Dallas/Maxim combo battery-clock-chip (still easy to obtain), as the old Moto 146818's are harder to find.

I wouldn't be concerned about U127--it's a commodity "glue" chip (74ALS00) and does not appear from the schematic to have anything to do with your problem.

Or you could try a new motherboard--but that's assuming that there aren't any software issues with processor speed, etc. You'd be safest replacing with another 6MHz 80286 board, but they're hard to find.

I do have an old Everex 286 motherboard that's a PC AT clone (no custom LSI chips) that should work. It doesn't have the 2 serial and parallel port onboard, so you'd need to find a serial/parallel card if your equipment uses those.

Since I'm not using it right now, I might consider a swap with your A Tease (seeing as I have the docs for the A Tease but not the Everex).

Hope this helps...
 
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I'd try cleaning the corrosion off with a brass bristle brush and some non-lubricating component cleaner first as it could be forming a high resistance short between adjacent pins.

Then do the same thing with a toothbrush to get in between the pins. Do both sides of the chip and you should reach most of the area under the chip and then give it a blast of cleaner all the way around the chip to blow out any residue.

Don't turn the machine on for about 10 minutes to allow it to warm back up.

If that doesn't clear up the problem, then a replacement is going to be necessary (or at least removing the chip to see if there are any damaged traces)
 
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