5.10.3 General-Purpose Input/Output Port (I/O)
Up to 44 I/O ports are implemented.
- P1, P2, P3, and P4 are full 8-bit ports; P5 and P6 feature up to 5-bit and 7-bit ports, respectively.
- All individual I/O bits are independently programmable.
- Any combination of input, output, is possible for P1, P2, P3, P4, P5, and P6. Interrupt conditions are possible in P1, P2, P3, and P4.
- Programmable pullup or pulldown on all ports.
- Edge-selectable interrupt and LPM3.5, LPM4 and LPM4.5 wake-up input capability is available in P1, P2, P3, and P4.
- Read and write access to port-control registers is supported by all instructions.
- Ports can be accessed byte-wise or word-wise in pairs.
Configuration of digital I/Os after BOR reset
To prevent cross currents during start-up of the device, all port pins are high-impedance with Schmitt triggers and module functions disabled. To enable the I/O functions after a BOR reset, first configure the ports and then clear the LOCKLPM5 bit. For details, see the Configuration After Reset section in the Digital I/O chapter of the MSP430FR4xx and MSP430FR2xx Family User's Guide.