
dsPIC33/PIC24 Family Reference Manual
DS30009711C-page 2
2006-2019 Microchip Technology Inc.
1.0
INTRODUCTION
The general purpose I/O pins can be considered the simplest of peripherals. They allow the PIC
®
MCU to monitor and control other devices. To add flexibility and functionality to a device, some
pins are multiplexed with alternate function(s). These functions depend on which peripheral
features are on the device. In general, when a peripheral is functioning, that pin may not be used
as a general purpose I/O pin.
Most of the dsPIC33/PIC24 devices support the Peripheral Pin Select (PPS) feature. The PPS
constitutes pins which users can map to the input and/or output of some digital peripherals.
shows a block diagram of a typical I/O port. This block diagram does not take into
account peripheral functions that may be multiplexed onto the I/O pin.
Figure 1-1:
Dedicated Port Structure Block Diagram
Note:
This family reference manual section is meant to serve as a complement to device
data sheets. Depending on the device variant, this manual section may not apply to
all dsPIC33/PIC24 devices.
Please consult the note at the beginning of the
“I/O Ports”
chapter in the current
device data sheet to check whether this document supports the device you are
using.
Device data sheets and family reference manual sections are available for
download from the Microchip Worldwide Website at:
http://www.microchip.com
WR LATx
TRISx Latch
I/O Pin
WR PORTx
Data Bus
Data Latch
Read LATx
Read PORTx
Read TRISx
WR TRISx
I/O Cell
Dedicated Port Module
0
1
Open-Drain Selection
Q
D
CK
Q
D
CK Q