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IBM PC 5150 memory expansion card issues please help

O

Ozfer

Experienced Member
Joined
Jan 15, 2014
Messages
82
Location
Connecticut USA
Hey guys its me again and I need more help with my 5150.

Today I am tackling the issue with my add in ram card on my 5150. On the pc motherboard I have the full 256K of ram with all the slots fully populated and the system works fine with that and boots to dos. I also have what I believe to be a DiamondFlower MF-100 Ram card. This card I think holds 384k ram and would allow my 5150 to reach the max of 640k ram since all 6 banks are populated but I am having a heck of a time trying to get it to work.

If I boot the IBM with the ram card in and set to just 256k RAM it will boot up fine with the card inserted, also the joystick port on the card works. If I set the jumpers on the motherboard to reflect the 640k or anything else above 256k (82 model motherboard so I believe the jumpers are ON off ON ON off for 640k) I get 407E 201 and then PARITY CHECK 2. Parity check 2 I think refers to the expansion card and the error code should be telling me what part of the memory is bad but I don't know how to diagnose that.

I have no clue if the jumpers on the expansion card are good and I have tried re seating all the memory chips on the MF-100. Maybe some of the ram chips could be bad? As can be seen in the pics I uploaded the board is slightly bent due to age but it's not awful, and also the battery that was on the expansion board leaked a bit and I scraped most of that off. Would it need a functioning battery to work and could that be the issue?

P1020602.jpgP1020597.jpgP1020599.jpgP1020600.jpgP1020605.jpg


The battery said Ni-CD 50Mah 3.6v can anyone confirm that this would work in its place?

Here are some details about the card I had a hard time understanding what it meant but I think they are the same card. As shown I switched the 6 pin block to what I believe to be the full amount but the switch block on the card doesn't say what position is on and off so I'm even unsure I have the card configured right. According to the jumper settings when I got the computer it was set to some weird amount of ram like 360K and I had no idea why. Please help :confused: I would upload more pics but I hit my limit already :S
http://www.angelfire.com/mn2/daveandkay/i/txt/54640.txt
http://www.angelfire.com/mn2/daveandkay/i/txt/52500.txt
http://www.ebay.com/itm/DIAMOND-FLO...NSION-CARD-NO-RAM-IBM-5150-5160-/300764702557
 
Battery will be for a battery backed up real time clock - not necessary for the RAM etc Just make sure to remove that old leaky one ASAP before it does damage.

I think the memory setting for that card is actually the start position - not how much RAM is installed.

Set the card to 256KB
SW1
On Off Off On Off Off

(taken from your first link, because the second link indicates a card with two serial ports)

If this works, it will tell the card to position it's 384KB of memory in the 256KB-640KB region.

Then set the 5150 to 640KB - so it knows how much to look for.

Then power it up and tell us what happens.
 
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Ozfer said:
The battery said Ni-CD 50Mah 3.6v can anyone confirm that this would work in its place?
Click to expand...
Confirmed, providing that the inter-pin distance is the same.
But as SpidersWeb wrote, the battery only supports the real time clock.

Ozfer said:
but the switch block on the card doesn't say what position is on and off
Click to expand...
Your card photo shows "ON" printed on the block. That is sure to mean that up is on.

Ozfer said:
Parity check 2 I think refers to the expansion card
Click to expand...
Yes, RAM on an expansion card.

Ozfer said:
and the error code should be telling me what part of the memory is bad but I don't know how to diagnose that.
Click to expand...
The code informs you of the failing address and within that address, the failing bits. See [here].
407E equates to bits 1/2/3/4/5/7 at address 256K.
From experience, 7 bits in error tells me that your 5150 found no RAM at address 256K.
So either a faulty card (the RAM component of it) or the card's jumpers are not set correctly.
 
Ha now I feel dumb I thought ONMG Japan meant it was some Japanese thing ;).

Okay so I set the card to On Off Off On Off Off and the motherboard to 640k and now I no longer get 407E 201 but I am now getting 6020 201 then PARITY CHECK 2 and after it looks for a floppy I get a line of gibberish.

I don't see a block 6 listed on the link to diagnose it could it be expansion board bank 3 or something and then 20 for bit 5 chip?
 
Success then, we're getting RAM off the card :) The error at 6020 could be why the previous owner set the motherboard to 384KB - perhaps that card has had a fault for a while.
6000 is the 384KB point.

Check you're moving the right chip. e.g. if pairty is at the top, then chips 1-8, you might've accidently moved chip 4 instead of 5.
 
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Provided the boards don't get held up in customs, 1st week of May is realistic. I will be offering a very low-volume assembly service, much the same as the ISA-CF and TRS-80 boards. Not too sure on pricing yet - some of the ICs are a bit pricey and I'm trying to find better pricing at the moment :)
 
Ozfer said:
Ha now I feel dumb I thought ONMG Japan meant it was some Japanese thing ;).
Click to expand...
I'm pretty sure there is a small space between the "ON" and the "MG"; easy to overlook. I was expecting it because switch block makers normally indicate on/off in some way, like [here].

Ozfer said:
I don't see a block 6 listed on the link to diagnose it
Click to expand...
I don't cater for every possible non-IBM RAM card that can be fitted; it is too much work (different bank counts, bank sizes, chip sizes, chip arrangements).

As SpidersWeb wrote, 6020 equates to the bit 5 chip at address 384K.

Because the expansion card starts at the 256K address, and each bank is 64K sized, the card's 6 banks appear in the machine's address space as follows (assumption: bank numbering starts at 0):

BANK 0: 256K to (320K-1)
BANK 1: 320K to (384K-1)
BANK 2: 384K to (448K-1) <-------- bit 5 here
BANK 3: 448K to (512K-1)
BANK 4: 512K to (576K-1)
BANK 5: 576K to (640K-1)

SpidersWeb said:
Check you're moving the right chip. e.g. if pairty is at the top, then chips 1-8, you might've accidently moved chip 4 instead of 5.
Click to expand...
Yes. This is where having the card's documentation helps.
 
OMG that's amazing now I want a new one :D. But for now I'm going to keep trying to get this to work.

I successfully set the machine to 384k and it doesn't get a parity error. yeay!

I'm not exactly sure what chip is the bad one though since I don't have the documentation that came with it. The bank numbering starts from left to right going from bank 1 to 6. I assume that means it would be on bank 3 and I am not sure what chip is for parity but I tried moving 4th 5th and 6th chip and I get the same error every time. To make things even more confusing the card has its own number system for each chip that goes from bottom to top left to right.

Then I just replaced every chip in the third row and put them in row 6. Now I am get 7010 201 sigh... so then I tried moving those chips to bank 6 and now I'm getting 807e 201 followed by a line of gibberish. Now I can set the system to boot with it set to 512k with no problem but nothing beyond that. Looks like I'm going to need new chips to get much further.
 
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SpidersWeb said:
(taken from your first link, because the second link indicates a card with two serial ports)
Click to expand...
Revisting this, as far as the switch block is concerned, I think the first link is wrong and the second correct.

Yes, the second link includes "serial ports (2)", but the remainder of the serial port information in that link only concerns one serial port. The "serial ports (2)" bit must be a mistake.

Second link

The second link's switch block info makes sense; 3 switches for start address and 3 for amount.

But as member MaTel discovered in 2008, there is an error in the link's table for switches S4/S5/S6. That discovery is in the thread [here]. For the card to provide 384 KB of RAM, S4/S5/S6 need to be set to ON/ON/OFF (not ON/ON/ON).
 
Okay based on the card jumper settings from the other guys thread I was able to correctly set the card to the max amount of memory.

I had ordered some replacement ram in the mail and today it came in, and now my 5150 is booting with full 640k :) Thanks for the help guys! Also I was able to replace the leaky battery with a new varta battery so that's all set also.
 
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