Up to ten 8-bit I/O ports are implemented: for 100-pin options, P1 through P10 are complete, and P11 contains three individual I/O ports. For 80-pin options, P1 through P7 are complete, P8 contains seven individual I/O ports, and P9 through P11 do not exist. Port PJ contains four individual I/O ports, common to all devices.
- All individual I/O bits are independently programmable.
- Any combination of input, output, and interrupt conditions is possible.
- Pullup or pulldown on all ports is programmable.
- Drive strength on all ports is programmable.
- Edge-selectable interrupt and LPM5 wake-up input capability is available for all bits of ports P1 and P2.
- Read and write access to port-control registers is supported by all instructions.
- Ports can be accessed byte-wise (P1 through P11) or word-wise in pairs (PA through PF).