6.4.1.5 Configuring Tri-State Functions (TRISx)

The TRISx registers configure the data direction flow through port I/O pins. The TRISx register bits determine whether a PORTx I/O pin is an input or an output:

• If a data direction bit is ‘1’, the corresponding I/O port pin is an input.
• If a data direction bit is ‘0’, the corresponding I/O port pin is an output.
• A read from a TRISx register reads the last value written to that register.
• All I/O port pins are defined as inputs after a Power-on Reset (POR).