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Help with 8-bit memory card

SunDown79

Veteran Member
Joined
Sep 8, 2005
Messages
783
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Netherlands
Hi,

I have this 8-bit memory card that I found in an IBM AT and I tried using it in my working IBM AT but I couldn't really get it to work.
So I was hoping anyone of you perhaps could tell me something more about it and even perhaps how to use it (it could be broken ofcourse).
It says to be a MMC T-2 card and its made in Taiwan so no famous brand or so.

I would especially like to know what the 4 switches do.

I have added some pictures.

Thanks Stefan.
 

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Chuck(G)

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It may have been used in an early 5170 (256KB or 512KB RAM on the motherboard) to fill memory out to 640K.

At any rate, you can be pretty sure that the DIP switches merely set the base address. I'd be very surprised if they didn't correspond in some fashion to the jumpers on the Everex Mini-Magic board.
 

Great Hierophant

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Mar 22, 2006
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It honestly looks like it is in the wrong system. Why put an 8-bit memory card in a 16-bit system? Moreover, with those 1-bit RAMs, you need another bank for 128Kx16. It does not look to be sophisticated enough to be an EMS card. It just looks like a RAM upgrade with 192Kx8 on it for a PC/XT. Maybe one of the banks can use 256Kx1 chips.
 

SunDown79

Veteran Member
Joined
Sep 8, 2005
Messages
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Well tried it with all settings but nothing changes, it either gives a 164 error (with no extra memory) or it gives a "parity check 2" with a bunch of question marks.
When I have time I will try it in my XT.
 

per

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Jan 21, 2008
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Western Norway
It may be one of these cards that were used to fill out the memory from 64KB to 256KB in early 16-64KB PCs, effectively making them into 64-256KB systems.

The DIP switches are connected to a piece of PROM, which is problably used to assign the different banks to given adresses (like how the IBM XT system-board handles the onboard RAM bank address assigning).
 

RJBJR

Experienced Member
Joined
Feb 17, 2011
Messages
453
I love a good mystery.
A search of google using the FCC ID FHG5UA MMC suggests it is manufactured by TMC.
 

dr.zeissler

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Joined
Jan 4, 2014
Messages
417
Location
Germany
hmm. I wanted to test area5150 on my Tandy1000, some scenes work, some don't. so I went for my EuroPC but than I realized that the demo requires more that 512KB RAM. I looked for a ram-extension and I found one without jumpers but that won't work due to a parity issue and that card above that also does not work. Did someone manage to get the correct jumper settings for the card in order to get 640KB Ram to watch area5150 on my EuroPC ?
 

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VERAULT

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Jan 30, 2012
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Got a working ram-expansion...but area5150 seem to be very exclusive for 5150 ;(
You are replying to an 11 year old dead thread ya know.

But if you want to have an easy working RAM card to bump your machine up to at least 512KB just go for the lo-tech card sold by texelec. I just bought one the other day for an early model 64KB 5150 I repaired. and recommended someone else on here buy one for thier 5150: https://texelec.com/product/lo-tech-1mb-ram/
 
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