DSPIC33FJ06GS101_12 Datasheet, PDF (155/386 Pages) Microchip Technology – 16-bit Digital Signal Controllers (up to 16 KB Flash and up to 2 KB SRAM) with High-Speed PWM, ADC, and Comparators

dsPIC33FJ06GS101/X02 and dsPIC33FJ16GSX02/X04
10.6 Peripheral Pin Select
Peripheral pin select configuration enables peripheral
set selection and placement on a wide range of I/O
pins. By increasing the pinout options available on a
particular device, programmers can better tailor the
microcontroller to their entire application, rather than
trimming the application to fit the device.
The peripheral pin select configuration feature operates
over a fixed subset of digital I/O pins. Programmers can
independently map the input and/or output of most
digital peripherals to any one of these I/O pins.
Peripheral pin select is performed in software, and gen-
erally does not require the device to be reprogrammed.
Hardware safeguards are included that prevent acciden-
tal or spurious changes to the peripheral mapping, once
it has been established.
10.6.1 AVAILABLE PINS
The peripheral pin select feature is used with a range
of up to 30 pins. The number of available pins depends
on the particular device and its pin count. Pins that
support the peripheral pin select feature include the
designation “RPn” in their full pin designation, where
“RP” designates a remappable peripheral and “n” is the
remappable pin number.
10.6.2 CONTROLLING PERIPHERAL PIN
SELECT
Peripheral pin select features are controlled through
two sets of Special Function Registers: one to map
peripheral inputs and another one to map outputs.
Because they are separately controlled, a particular
peripheral’s input and output (if the peripheral has both)
can be placed on any selectable function pin without
constraint.
The association of a peripheral to a peripheral select-
able pin is handled in two different ways, depending on
whether an input or output is being mapped.
10.6.2.1 Input Mapping
The inputs of the peripheral pin select options are
mapped on the basis of the peripheral. A control
register associated with a peripheral dictates the pin it
will be mapped to. The RPINRx registers are used to
configure peripheral input mapping (see Register 10-1
through Register 10-14). Each register contains sets of
6-bit fields, with each set associated with one of the
remappable peripherals. Programming a given
peripheral’s bit field with an appropriate 6-bit value
maps the RPn pin with that value to that peripheral. For
any given device, the valid range of values for any bit
field corresponds to the maximum number of peripheral
pin selections supported by the device.
Figure 10-2 Illustrates remappable pin selection for
U1RX input.
Note:
For input mapping only, the Peripheral Pin
Select (PPS) functionality does not have
priority over the TRISx settings. There-
fore, when configuring the RPx pin for
input, the corresponding bit in the TRISx
register must also be configured for input
(i.e., set to ‘1’).
FIGURE 10-2:
REMAPPABLE MUX
INPUT FOR U1RX
U1RXR<5:0>
0
RP0
1
RP1
U1RX Input
2 ^{to Peripheral}
RP2
33
RP33
© 2008-2012 Microchip Technology Inc.
DS70318F-page 155