Sound like you have the right mindset ;-) The most boring part of the project was routing of all the bus lines in KiCad, but I knew that if a kept on working, t

Sound like you have the right mindset ;-) The most boring part of the project was routing of all the bus lines in KiCad, but I knew that if a kept on working, the reward would be big :-) I was actually planning to do a ROM emulator with a PIC MCU at first, but ended up using a regular EPROM, SIO/UART and a bootloader to load programs via RS232. When I had a stable program, I burned it to the ROM and continued. This is because when I got started with the "test circuit" I didn't want to go back to the PIC :-D I'm currently developing my ROM monitor so that I can get CP/M running :-)