The following table lists the main I/O definitions of the Pecom 64.
- Cassette Out
- Serial print out
- Display / Non display period (valid if OUT1 bit 1 = 1)
- EF1 = 1 if CTRL key pressed (valid if OUT1 bit 1 = 0)
- Cassette In
- Serial printer ready (valid if OUT1 bit 1 = 1)
- EF2 = 1 if SHIFT key pressed (valid if OUT1 bit 1 = 0)
|EF3||EF3 = 1 if CAPS key pressed|
|EF3||EF4 = 0 if BREAK key pressed|
At startup of the computer the ROM is mapped from @0000-@7FFF and @8000-@FFFF however this is changed by the first OUT 1 instruction at which time the RAM is mapped from @0000-@7FFF.
bit 1 = 1 in select the video RAM, bit 1 = 0 select ROM at address @F400-@FFFF
|OUT 3-7||1870 OUT 3 to 7|
|INP 3||Keyboard input|