16.1 Overview

Each port has eight registers to control the operation. These registers are:

• PORTx registers (reads the levels on the pins of the device)
• LATx registers (output latch)
• TRISx registers (data direction)
• ANSELx registers (analog select)
• WPUx registers (weak pull-up)
• INLVLx (input level control)
• SLRCONx registers (slew rate control)
• ODCONx registers (open-drain control)

In this section, the generic names such as PORTx, LATx, TRISx, etc. can be associated with PORTA, PORTB, PORTC, etc., depending on availability per device.

A simplified model of a generic I/O port, without the interfaces to other peripherals, is shown in the following figure: