User manual

MPLAB
®
X PICkit™ 3 User’s Guide
DS52116A-page 36  2013 Microchip Technology Inc.
FIGURE 4-1: CONNECTING THE DEMO BOARD TO THE PICkit™ 3
4.3.3 Configuration Bits and Debug Express
PIC microcontroller devices that do not require an ICD Header and may be debugged
directly contain a DEBUG
bit in the Configuration Word(s) that enables and disables
the Debug mode on the PIC microcontroller.
This bit is automatically set appropriately by the MPLAB X IDE when using PICkit 3
Debug Express and should not be specified in source code configuration settings.
Many 16-bit PIC microcontroller devices such as PIC24 and dsPIC33 families have
multiple ICSP programming and debugging port pins labeled PGC1/EMUC1 and
PGD1/EMUD1, PGC2/EMUC2 and PGD2/EMUD2, etc. While any ICSP port may be
used for programming, only one port is active at a time for debugging. The active EMU
port is set in the device Configuration bits. If the active port setting does not match the
EMU port to which the PICkit 3 is connected, the device will be unable to enter Debug
mode. In the MPLAB X IDE Configuration Bits dialog, these bits are usually referred to
as the “Comm Channel Select” bits.
CAUTION
The DEBUG Configuration bit value should not be specified in source code Configura-
tion settings under normal conditions. Doing so may cause the bit to be asserted when
programming a device outside the debugger. This will cause the device to function
improperly, or not at all, in the application circuit.