REimplement a MEMOTECH compatible computer

Updated to revision r3, supporting a daughter board, enabling printer support, proper pin compatible port 7 support, external ROM 2 support, and improved secondary VGA support. Also supporting a serial port.

REMEMOTECH is a modern-day re-implementation of a Memotech MTX/FDX/SDX compatible computer :-

It implements enough hardware to allow it to run MTX BASIC, various MTX games and CP/M. It supports :-

It was developed because I had previously implemented the MEMU Memotech emulator and this was the next logical challenge. As a starting point, I knew nothing about VHDL or hardware design. It was a great learning opportunity.

REMEMOTECH reproduces most of the MTX functionality, including some from FDX and and some from SDX. New features have been added where existing software is able to benefit from them.

The implementation tries to stick to non-vendor specific VHDL, avoids vendor megafunctions, and might work with some tweaks on other boards or vendor technologies. A few Quartus specific features are needed in order to squeeze REMEMOTECH into the Altera DE1 board (these are commented as such in the code).

REMEMOrizer is an attempt to apply the technology developed here to create an add-on for Memotech owners.