Casio FX-602P Ram Upgrade looking for srams

[blackjetrock]

Quote:Alternatively, is there enough space inside to put a small microcontroller on a board that presents as the necessary circuit? Even a small controller should have enough SRAM to give you several banks. Obviously it's more work since you have to build it and program it, but long-term it might be easier to maintain and find parts.

Cheers,

--Aaron

There's enough room to replace the entire calculator PCB with a different PCB with a
microcontroller on it:

https://www.youtube.com/watch?v=5w6tmykqrYM&t=4s

As the ROM for the 502 or 602 hasn't been dumped yet to my knowledge the code
has to be re-written.

You could probably replace the RAM chip with an RP2040 as here:

https://www.youtube.com/watch?v=XirGbH-HYOA&t=6s

With an RP2040 and similar code to that RAM replacement you could use some of the 260K or so of RAM and even the 2M of flash as storage. An extra SD card could also be added to save the RAM contents.
If the 602 runs at 5V then you might even be able to get away with no level shifters as in the RAM replacement above.
Andrew