6.9.4 Digital I/O
There are ten 8-bit I/O ports implemented—ports P1 through P10:
- All individual I/O bits are independently programmable.
- Any combination of input, output, and interrupt conditions is possible.
- Edge-selectable interrupt input capability for all the eight bits of ports P1 and P2.
- Read and write access to port-control registers is supported by all instructions
- Ports P7/P8 and P9/P10 can be accessed word-wise as ports PA and PB, respectively.