I/O Map
The following table lists the main I/O definitions of the Pecom 64.
| Q |
- Cassette Out - Serial print out |
| EF1 |
- Display / Non display period (valid if OUT1 bit 1 = 1) - EF1 = 1 if CTRL key pressed (valid if OUT1 bit 1 = 0) |
| EF2 |
- 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 |
| OUT 1 |
Select Bank 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 |