pic32mx320f064h Microchip Technology Inc., pic32mx320f064h Datasheet - Page 495

• Manufacturer Part Number: pic32mx320f064h
• Description: 64/100-pin General Purpose, 32-bit Flash Microcontrollers
• Manufacturer: Microchip Technology Inc.

FIGURE 27-3:
In PIC32MX Family devices, the hardware for the JTAG
boundary scan is implemented as a peripheral module
(i.e., outside of the CPU core) with additional integrated
logic in all I/O ports. A logical block diagram of the
JTAG module is shown in Figure 27-1. It consists of the
following key elements:
• TAP Interface Pins (TDI, TMS, TCK and TDO)
• TAP Controller
• Instruction Shift register and Instruction Register
• Data Registers (DR)
27.2.4.1
The Test Access Port (TAP) on the PIC32MX Family
device is a general purpose port that provides test
access to many built-in support functions and test logic
defined in IEEE 1149.1. The TAP is enabled by the
JTAGEN bit in the DDPCON register. The TAP is
enabled, JTAGEN = 1, by default when the device exits
Power-on-Reset (POR) or any device Reset. Once
enabled, the designated I/O pins become dedicated
TAP pins.
© 2007 Microchip Technology Inc.
(IR)
Controller
JTAG
Test Access Port (TAP) and TAP
Controller
TDO
TMS
TCK
TDI
OVERVIEW OF PIC32MX FAMILY-BASED JTAG COMPLIANT APPLICATION
SHOWING DAISY-CHAINING OF COMPONENTS
JTAG Connector
Advance Information
PIC32MX
The PIC32MX Family implements a 4-pin JTAG
interface with these pins:
• TCK (Test Clock Input): Provides the clock for test
• TMS (Test Mode Select Input): Used by the TAP
• TDI (Test Data Input): Serial input for test
• TDO (Test Data Output): Serial output for test
27.2.4.2
The JTAG module uses a number of registers of vari-
ous sizes as part of its operation. In terms of bit count,
most of the JTAG registers are single bit register cells,
integrated into the I/O ports. Regardless of their loca-
tion within the module, none of the JTAG registers are
located within the device data memory space, and
cannot be directly accessed by the user in normal
operating modes.
logic.
to control test operations.
instructions and data.
instructions and data.
PIC32MX Device-Based Application
PIC32MX FAMILY
JTAG Registers
JTAG compliant
PIC32MX
(or other
device)
DS61143A-page 493