I/O Map
The following table lists the main I/O definitions of the Cosmicos and some additional HW. Note that I/O would off course only work if specified HW is connected.
Q
- Speaker, where frequency of switching Q gives a square wave tone
- Sound on/off (when CDP1864 sound is used)
- Cassette out
- Video Terminal Serial output
EF1
RET button hex keypad
EF2
- DEC and SEQ button hex keypad
- Cassette in
EF3
- REQ and SEQ button hex keypad
- CDP 1864 display
EF4
Video Terminal serial input
OUT 2
Q=1, CDP 1864: tone Latch
OUT 5
Select row hex keypad
OUT 6
Set active 7 segment display digit
OUT 7
Set main board display digits
INP 1
Q=0, CDP 1864 display: display on
INP 2
Q=0, CDP 1861 display: display off
INP 5
Select column hex keypad
INP 6
Reset 7 segment display counter to first digit
INP 7
Main board data switches input