k2x4b524[
Veteran Member
4040 201, is the error code it give me when i put in my ast sixpack plus, i know 201 is a memory parity error, but the 4040? is that the chip location ON the sixpack card?
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IBM 5150 Parity Errors
- Thread starter k2x4b524[
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k2x4b524[
Veteran Member
Scratch that, i THOUGHT i had a solution found
It's giving me a code of Party Check 2 now
.
It's giving me a code of Party Check 2 now
.
Last edited:
per
Veteran Member
4040 refers to what bank of memory that fails, and what pattern it fails on. What the numbers actually means varies from what BIOS you got.
You can know that the AST is failing if you don't get the error by removing the AST (remember to set the motherboard switches accordingly). In order to fix it, you will have to replace that one chip. After you have decoded the number, you should use the bank number to find the bank where it fails, and the failing test-pattern to find what of the chips in that bank you should replace.
I don't remember the decoding in my head, but I am quite sure you can find it by a quick web search.
You can know that the AST is failing if you don't get the error by removing the AST (remember to set the motherboard switches accordingly). In order to fix it, you will have to replace that one chip. After you have decoded the number, you should use the bank number to find the bank where it fails, and the failing test-pattern to find what of the chips in that bank you should replace.
I don't remember the decoding in my head, but I am quite sure you can find it by a quick web search.
modem7
10k Member
ASSUMPTION: You have the 64/256K version of the 5150 motherboard, and it's RAM sockets are fully populated.
The '4040' in '4040 201' indicates: Bit 2 failure in the 64K block of RAM starting at 256K. That block of RAM is on your SixPakPlus (if it has been set up to start it's RAM at 256K). The '2' in 'Parity Check 2' is also a pointer to the RAM error being off the motherboard (if motherboard switches set correctly).
Possibilities:
1. The bit 2 chip in the first 64K block of RAM on your SixPakPlus is indeed faulty.
2. The switches on your SixPakPlus are not set to start the RAM at address 256K.
3. Your SixPakPlus is faulty - the RAM is good and switches set correctly, but a fault means that the RAM is not being seen.
Because of an issue I've seen with my SixPakPlus, if the motherboard's 8088 has been replaced with a V20, or other form of speed-up, then try putting the 8088 back in.
k2x4b524[
Veteran Member
Awesome 
Thank you, one of the chips was in fact bad on my sixpackplus,i also found this site http://www.ibm5150.net/index.html which led me to a document that went over it in a little detail. the chips on the sixpack are a soup of a chips going from 200ns to 120ns, so i'm expecting some more to wear out soon, but it works now, and now i know how to translate what the pc is saying. Again Thank you
Thank you, one of the chips was in fact bad on my sixpackplus,i also found this site http://www.ibm5150.net/index.html which led me to a document that went over it in a little detail. the chips on the sixpack are a soup of a chips going from 200ns to 120ns, so i'm expecting some more to wear out soon, but it works now, and now i know how to translate what the pc is saying. Again Thank you
Chuck(G)
25k Member
Bit 2? How does that work? I would have thought it to be bit 6.
per
Veteran Member
Found the decoding table now.
The first two digits refers to what 16Kb bank of memory is failing. On a 64-256KB board, the system RAM is 00->3F (00->0F for a 16-64KB board), so 40 means the bank starting at absolute address 40000 (hexadecimal, 256K in decimal, or the first bank above the system memory).
The last two diggits does indicate what bits are failing, in this case only bit 6 (as said above).
To check if it's right, just place a working chip on top of the failing module. If the error dissapears, then you know that exact chip is the problem, and you can entirely replace it with the working chip. However, in your case, you should check all the jumpers first just to make sure the bank that should have been at absolute address 256K actually is mapped to absolute address 256K.
I don't think it's too severial mixing RAm speeds for such old machines. Remember that 6164 DRAM don't have special timimg-sensitive functions like Fast-page or EDO, and the only requirement is that they will have to be faster or equal to 200ns. I have allways found it wise to keep some spare; Appromaxely 100 working pieces in my case (so far, I have needed one).
The first two digits refers to what 16Kb bank of memory is failing. On a 64-256KB board, the system RAM is 00->3F (00->0F for a 16-64KB board), so 40 means the bank starting at absolute address 40000 (hexadecimal, 256K in decimal, or the first bank above the system memory).
The last two diggits does indicate what bits are failing, in this case only bit 6 (as said above).
To check if it's right, just place a working chip on top of the failing module. If the error dissapears, then you know that exact chip is the problem, and you can entirely replace it with the working chip. However, in your case, you should check all the jumpers first just to make sure the bank that should have been at absolute address 256K actually is mapped to absolute address 256K.
I don't think it's too severial mixing RAm speeds for such old machines. Remember that 6164 DRAM don't have special timimg-sensitive functions like Fast-page or EDO, and the only requirement is that they will have to be faster or equal to 200ns. I have allways found it wise to keep some spare; Appromaxely 100 working pieces in my case (so far, I have needed one).
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modem7
10k Member
Doh! The batteries in my calculator need replacing again.
Note for readers that whether this method works or not depends on the type of failure of the RAM chip. It's been discussed in earlier threads. Certainly worth a try though.
k2x4b524[
Veteran Member
All is good with it now, all is right and my 5150 stopped bitching. Next project with it, undocumented DIP switch settings to allow up to 736kb conventional ram by using the gaps left in the upper addresses. good thing my quadram quadboard supports ram starting points up to 960kb :D
There's a program I came across... perhaps it could be of use to you?
http://www.mediafire.com/file/mzrim0ywl0q/704k.zip
http://www.mediafire.com/file/mzrim0ywl0q/704k.zip