Simple monitor program for my z80-breadboard-computer and the closely related BeanZee Z80 development board.
Memory map:
0000 - 7FFF : 32k ROM
8000 - FFFF : 32k RAM
Buffer starts at bottom of RAM (8000)
Stack starts at top of RAM (FFFF) (working down)
The program expects to find an FTDI UM245R USB to Parallel FIFO Development Module at ports 0 and 1:
Port 0 : status (read only)
Port 1 : data (read / write)
Status byte:
Bit 0 : device ready for data to be written (active low)
Bit 1 : data available in read buffer (active low)