In another thread, I discussed a few issues I had with my new IBM PC/AT.
Inside the computer was an Intel Above Board containing 640k of memory. This, plus the 512k onboard made for 640k base and 512k expanded (forgive me if I get the terms wrong).
I have 16 more 256kbit (total of 512k) memory chips that I would like to add to make 640k base, 1MB expanded.
The problem I face is the DIP switches for configuring the memory board. They are pre-configured for the current 640k configuration. That config contains 16 64kbit chips in banks 1 and 2, and 16 256kbit chips in banks 3 and 4. If anyone has the schematics or switch settings, please share. Here is a picture of the board.
Inside the computer was an Intel Above Board containing 640k of memory. This, plus the 512k onboard made for 640k base and 512k expanded (forgive me if I get the terms wrong).
I have 16 more 256kbit (total of 512k) memory chips that I would like to add to make 640k base, 1MB expanded.
The problem I face is the DIP switches for configuring the memory board. They are pre-configured for the current 640k configuration. That config contains 16 64kbit chips in banks 1 and 2, and 16 256kbit chips in banks 3 and 4. If anyone has the schematics or switch settings, please share. Here is a picture of the board.