I/O Map
The following table lists the main I/O definitions of the Cosmac VIP and some additional HW. Note that I/O would off course only work if specified HW is connected.
Q
- Sound on/off: fixed tone, VP595 or VP550 depending on configuration
- Cassette out
- Printer: strobe
EF1
CDP 1861 display / VP590 Colour Board: display status
EF2
Casssette in
EF3
- Keyboard pressed
- Printer: busy
EF4
VP580 Expansion Keyboard pressed
OUT 1
CDP 1861 display / VP590 Colour Board: display off
OUT 2
Key latch
OUT 3
- VP595 Simple Sound Board: Tone latch
- Printer: latch
OUT 4
Address latch, after any OUT 4 RAM will be mapped at address @0000 instead of ROM
OUT 5
VP590 Colour Board: step background colour
INP 1
CDP 1861 display / VP590 Colour Board: display on