Datasheet

dsPIC33EPXXXGM3XX/6XX/7XX
DS70000689D-page 174  2013-2014 Microchip Technology Inc.
6. The Peripheral Pin Select (PPS) pin mapping
rules are as follows:
a) Only one “output” function can be active on a
given pin at any time, regardless if it is a
dedicated or remappable function (one pin,
one output).
b) It is possible to assign a “remappable output”
function to multiple pins and externally short
or tie them together for increased current
drive.
c) If any “dedicated output” function is enabled
on a pin, it will take precedence over any
remappable “output” function.
d) If any “dedicated digital” (input or output) func-
tion is enabled on a pin, any number of “input”
remappable functions can be mapped to the
same pin.
e) If any “dedicated analog” function(s) are
enabled on a given pin, “digital input(s)” of any
kind will all be disabled, although a single “dig-
ital output”, at the user’s cautionary discretion,
can be enabled and active as long as there is
no signal contention with an external analog
input signal. For example, it is possible for the
ADCx to convert the digital output logic level
or to toggle a digital output on a comparator or
ADCx input provided there is no external
analog input, such as for a built-in self-test.
f) Any number of “input” remappable functions
can be mapped to the same pin(s) at the
same time, including to any pin with a single
output from either a dedicated or remappable
“output”.
g) The TRIS registers control only the digital I/O
output buffer. Any other dedicated or remap-
pable active “output” will automatically override
the TRIS setting. The TRIS register does not
control the digital logic “input” buffer. Remap-
pable digital “inputs” do not automatically
override TRIS settings, which means that the
TRIS bit must be set to input for pins with only
remappable input function(s) assigned.
h) All analog pins are enabled by default after
any Reset and the corresponding digital input
buffer on the pin is disabled. Only the Analog
Pin Select registers control the digital input
buffer, not the TRIS register. The user must
disable the analog function on a pin using the
Analog Pin Select registers in order to use any
“digital input(s)” on a corresponding pin, no
exceptions.