www.ti.com
P
6.24 IEEE 1149.1 JTAG
6.24.1
JTAG ID (JTAGID) Register Description(s)
TMS320DM6437
Digital Media Processor
SPRS345B–NOVEMBER 2006–REVISED MARCH 2007
The JTAG
(3)
interface is used for BSDL testing and emulation of the DM6437 device.
TRST only needs to be released when it is necessary to use a JTAG controller to debug the device or
exercise the device's boundary scan functionality.
Note
: TRST is synchronous and
must
be clocked by
TCK; otherwise, the boundary scan logic may not respond as expected after TRST is asserted.
For maximum reliability, DM6437 includes an internal pulldown (IPD) on the TRST pin to ensure that
TRST will always be asserted upon power up and the device's internal emulation logic will always be
properly initialized.
JTAG controllers from Texas Instruments actively drive TRST high. However, some third-party JTAG
controllers may not drive TRST high but expect the use of a pullup resistor on TRST.
When using this type of JTAG controller, assert TRST to initialize the device after powerup and externally
drive TRST high before attempting any emulation or boundary scan operations.
(3)
IEEE Standard 1149.1-1990 Standard-Test-Access Port and Boundary Scan Architecture.
Table 6-114. JTAG ID (JTAGID) Register
HEX ADDRESS RANGE
ACRONYM
REGISTER NAME
COMMENTS
Read-only. Provides 32-bit
JTAG ID of the device.
0x01C4 0028
JTAGID
JTAG Identification Register
The JTAG ID register is a read-only register that identifies to the customer the JTAG/Device ID. For the
DM6437 device, the JTAG ID register resides at address location 0x01C4 0028. For the actual register bit
names and their associated bit field descriptions, see
Figure 6-58
and
Table 6-115
.
31-28
27-12
11-1
0
VARIANT (4-Bit)
PART NUMBER (16-Bit)
MANUFACTURER (11-Bit)
LSB
R-n
R-1011 0111 0010 0001
R-0000 0010 111
R-1
LEGEND: R = Read, W = Write, n = value at reset
Figure 6-58. JTAG ID (JTAGID) Register—0x01C4 0028
Table 6-115. JTAG ID (JTAGID) Register Selection Bit Descriptions
BIT
NAME
DESCRIPTION
Variant (4-Bit) value. The value of this field depends on the device silicon revision being used. For
more information, see the
TMS320DM6437/35/33/31 Digital Media Processor (DMP) [Silicon
Revisions 1.1 and 1.0] Silicon Errata
(literature number
SPRZ250
).
Part Number (16-Bit) value. DM6437 value: 1011 0111 0010 0001.
Manufacturer (11-Bit) value. DM6437 value: 0000 0010 111.
LSB. This bit is read as a "1" for DM6437.
31:28
VARIANT
27:12
11-1
0
PART NUMBER
MANUFACTURER
LSB
Peripheral Information and Electrical Specifications
302
Submit Documentation Feedback