S/UNI-IMA-4 Telecom Standard Product Data Sheet
Released
10.6 JTAG Test Access Port
The JTAG Test Access Port block provides JTAG support for boundary scan. The standard
JTAG EXTEST, SAMPLE, BYPASS, IDCODE and STCTEST instructions are supported. The
S/UNI-IMA-4 identification code is 173400CD hexadecimal.
10.6.1 JTAG Support
The S/UNI-IMA-4 supports the IEEE Boundary Scan Specification as described in the IEEE
1149.1 standards. The Test Access Port (TAP) consists of the five standard pins; TRSTB, TCK,
TMS, TDI and TDO used to control the TAP controller and the boundary scan registers. The
TRSTB input is the active-low reset signal used to reset the TAP controller. TCK is the test
clock used to sample data on input, TDI and to output data on output, TDO. The TMS input is
used to direct the TAP controller through its states. The basic boundary scan architecture is
shown below.
Figure 27 Boundary Scan Architecture
Boundary Scan
TDI
Register
Device Identification
Register
Bypass
Register
Instruction
Register
and
Mux
DFF
TDO
Decode
Control
TMS
Test
Access
Port
Select
Controller
Tri-state Enable
TRSTB
TCK
Proprietary and Confidential to PMC-Sierra, Inc., and for its customers’ internal use.
Document No.: PMC-2020889, Issue 2
86
PMC [ PMC-SIERRA, INC ]
