Hi, I enjoy playing with my new/old T100 and want to start doing some hardware hacking with its system bus.
According to the docs, REXCPM can disable <https://bitchin100.com/wiki/index.php?title=REXCPM#Overview> the built-in RAM and shadow the internal ram with its own banked RAM. Since I consider doing some RAM banking without pulling out the original RAM or sneaking in an extra wire or resistor and wondering how that can be achieved. It would mean that we need to switch off the internal RAM. But looking at the schematic <https://github.com/hzeller/trs80-100-schematic>, it looks like options would be to * Either make sure that none of the chip enable signals for the RAM ever go to zero, but they are under control of M3 and M4 and this looks infeasible * We could force pull the RAMRST signal to high, but I suppose that would make transistor T9 not very happy. So also not feasible * The option that I missed :) How is this done in REXCPM ? Thanks, Henner.
