
dsPIC33EPXXXGP50X, dsPIC33EPXXXMC20X/50X, AND PIC24EPXXXGP/MC20X
DS70657E-page 382
Preliminary
2011-2012 Microchip Technology Inc.
27.6
JTAG Interface
dsPIC33EPXXXGP50X, dsPIC33EPXXXMC20X/50X,
and PIC24EPXXXGP/MC20X devices implement a
JTAG interface, which supports boundary scan device
testing. Detailed information on this interface is
provided in future revisions of the document.
27.7
In-Circuit Serial Programming
The dsPIC33EPXXXGP50X, dsPIC33EPXXXMC20X/
50X, and PIC24EPXXXGP/MC20X devices can be
serially programmed while in the end application circuit.
This is done with two lines for clock and data and three
other lines for power, ground and the programming
sequence. Serial programming allows customers to
manufacture boards with unprogrammed devices and
then program the device just before shipping the
product. Serial programming also allows the most recent
firmware or a custom firmware to be programmed. Refer
to
the
“dsPIC33E/PIC24E
Flash
Programming
Specification for Devices with Volatile Configuration Bits”
(DS70663)
for
details
about
In-Circuit
Serial
Programming (ICSP).
Any of the three pairs of programming clock/data pins
can be used:
PGEC1 and PGED1
PGEC2 and PGED2
PGEC3 and PGED3
27.8
In-Circuit Debugger
When MPLAB ICD 3 or REAL ICE is selected as a
debugger, the in-circuit debugging functionality is
enabled. This function allows simple debugging func-
tions when used with MPLAB IDE. Debugging function-
ality is controlled through the PGECx (Emulation/
Debug Clock) and PGEDx (Emulation/Debug Data) pin
functions.
Any of the three pairs of debugging clock/data pins can
be used:
PGEC1 and PGED1
PGEC2 and PGED2
PGEC3 and PGED3
To use the in-circuit debugger function of the device,
the design must implement ICSP connections to
MCLR, VDD, VSS, and the PGECx/PGEDx pin pair. In
addition, when the feature is enabled, some of the
resources are not available for general use. These
resources include the first 80 bytes of data RAM and
two I/O pins (PGECx and PGEDx).
27.9
Code Protection and
CodeGuard Security
The dsPIC33EPXXXGP50X, dsPIC33EPXXXMC20X/
50X, and PIC24EPXXXGP/MC20X devices offer basic
implementation of CodeGuard Security that supports
only General Segment (GS) security. This feature helps
protect individual Intellectual Property.
Note:
Refer to Section 24. “Programming and
Diagnostics”
(DS70608)
of
the
“dsPIC33E/PIC24E
Family
Reference
Manual” for further information on usage,
configuration and operation of the JTAG
interface.
Note:
Refer to Section 23. “CodeGuard
Security” (DS70634) of the “dsPIC33E/
PIC24E Family Reference Manual” for
further
information
on
usage,
configuration
and
operation
of
CodeGuard Security.