Up to eight 8-bit I/O ports are implemented—ports P1 to P8:
- All individual I/O bits are independently programmable.
- Any combination of input, output, and interrupt condition is possible.
- Edge-selectable interrupt input capability for all 8 bits of both port P1 and port P2.
- Read and write access to port-control registers is supported by all instructions.
- Each I/O has an individually programmable pullup or pulldown resistor.
- Ports P7 and P8 can be accessed word-wise.