16.1 Overview
Device | PORTA | PORTB | PORTC | PORTD | PORTE |
---|---|---|---|---|---|
28-pin devices | ● | ● | ● | ● | |
40/44-pin devices | ● | ● | ● | ● | ● |
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: