Datasheet

© 2007-2012 Microchip Technology Inc. DS70291G-page 341
dsPIC33FJ32MC302/304, dsPIC33FJ64MCX02/X04 AND dsPIC33FJ128MCX02/X04
28.5 JTAG Interface
The dsPIC33FJ32MC302/304, dsPIC33FJ64MCX02/
X04 and dsPIC33FJ128MCX02/X04 devices
implement a JTAG interface, which supports boundary
scan device testing, as well as in-circuit programming.
Detailed information on this interface is provided in
future revisions of the document.
28.6 In-Circuit Serial Programming
The dsPIC33FJ32MC302/304, dsPIC33FJ64MCX02/
X04 and dsPIC33FJ128MCX02/X04 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 digital signal controller just before
shipping the product. Serial programming also allows
the most recent firmware or a custom firmware to be
programmed. Refer to the “dsPIC33F/PIC24H Flash
Programming Specification” (DS70152) 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
28.7 In-Circuit Debugger
When MPLAB
®
ICD 3 is selected as a debugger, the
in-circuit debugging functionality is enabled. This
function allows simple debugging functions when used
with MPLAB IDE. Debugging functionality 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, PGC, PGD 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.
28.8 Code Protection and CodeGuard
Security
The dsPIC33FJ64MCX02/X04 and
dsPIC33FJ128MCX02/X04 devices offer advanced
implementation of CodeGuard Security that supports
BS, SS and GS while, the dsPIC33FJ32MC302/304
devices offer the intermediate level of CodeGuard
Security that supports only BS and GS. CodeGuard
Security enables multiple parties to securely share
resources (memory, interrupts and peripherals) on a
single chip. This feature helps protect individual
Intellectual Property in collaborative system designs.
When coupled with software encryption libraries,
CodeGuard Security can be used to securely update
Flash even when multiple IPs reside on the single chip.
The code protection features vary depending on the
actual dsPIC33F implemented. The following sections
provide an overview of these features.
Secure segment and RAM protection is implemented
on the dsPIC33FJ64MCX02/X04 and
dsPIC33FJ128MCX02/X04 devices. The
dsPIC33FJ32MC302/304 devices do not support
secure segment and RAM protection.
Note: Refer to Section 24. “Programming and
Diagnostics” (DS70207) of the
dsPIC33F/PIC24H Family Reference
Manual for further information on usage,
configuration and operation of the JTAG
interface.
Note: Refer to Section 23. “CodeGuard™
Security” (DS70199) of the “dsPIC33F/
PIC24H Family Reference Manual” for
further information on usage,
configuration and operation of
CodeGuard Security.