I have a few 32K memory modules I’m testing that another list member came up with. One design is 32K of FRAM and plugs into the #3 socket and you run a few wires to pick up the other needed signals. The other plugs into the System bus socket. Both take over all 32K of RAM address space.
I suspect your design should work too. The only tricky thing will be lining up all the pins into the various RAM sockets. I seem to recall that some machines came with multiple RAM modules soldered on as well, so it won’t work for those probably. I’m guessing these were just the later models though? Jeff Birt From: M100 <[email protected]> On Behalf Of Stephen Adolph Sent: Sunday, March 14, 2021 6:19 PM To: [email protected] Subject: [M100] why has no one ever made a 24kB RAM module for M100? Seems like such a thing is long overdue. The 3801 8k variant is very common. I made up a board today to test. It has a single 128kB SRAM chip, and some logic to decode the 12 (16) /CE signals into address lines. In fact it is a 32k capable module, with the usual case being 24kB. the rightmost section is something that can be cut away to fit into a 24kB machine. (If like me you actually have a use for a 32kB memory module, then this can do it too. What use? fast SRAM for 2x clock rate) I'll send it out for boards and see if it works. Steve
