6 août 2011


This card is made in Taiwan. The S/N is 030267. There is a set of jumpers nearby, but I have no information concerning the configuration setting to reach 4 Megabytes as mentioned on the card.

Components for the memory are written : TTC511000P-10 : Please find hereunder the message received from Bill concerning the setting of the jumpers.

I have a GS Ram card like yours which I recently picked up on eBay.  I came across your web site while trying to locate some information on the board. I spent much of today getting it to work.  It had a burned out chip on it (looks like someone tried to put it into a slot instead of into the memory expansion socket).  One of the chips was burned so badly I had to replace the socket as it was melted. After replacing the socket and the chip (I used a 74ACT04 to replace the 74F04 and it seems to be fine), I began to test it out.

My card came with 2 megabytes of memory on it.  I ran a memory tester from on it and it passed.  I had some 1 megabyte DRAM chips in stock, so I added another 1 megabyte to it and tried to configure it for 3 megabytes.  After several hours of not being able to make it work, I went back into my lab and began to trace all of the address and chip select lines on the ram chips in order to figure out how to properly configure it.  I then realized that the card can only be configured for 1, 2, or 4 megabytes.

I scavenged some more 1 megabyte DRAM chips to fill the board up with a full 4 megabytes.  After setting the jumpers, I started up the memory test program and finally I was greeted with success.

I thought perhaps you might like the jumper settings for your board.  RAM expansion boards for Apple IIgs computers are a bit scarce today, so I think you will want to hold onto yours if you still get any enjoyment out of the GS.

J1=open, J2=open --> use bank 1 of memory only

J1=open, J2=shorted --> use bank 1 and 2 of memory only

J1=shorted, J2=open --> invalid

J1=shorted, J2=shorted --> use all 4 banks of memory

- Bill Dorsey