S/UNI®-JET Data Sheet
Released
The test logic reset state is used to disable the TAP logic when the device is in normal mode
operation. The state is entered asynchronously by asserting input, TRSTB. The state is entered
synchronously regardless of the current TAP controller state by forcing input, TMS high for 5
TCK clock cycles. While in this state, the instruction register is set to the IDCODE instruction.
Run-Test-Idle
The run test/idle state is used to execute tests.
Capture-DR
The capture data register state is used to load parallel data into the test data registers selected by
the current instruction. If the selected register does not allow parallel loads or no loading is
required by the current instruction, the test register maintains its value. Loading occurs on the
rising edge of TCK.
Shift-DR
The shift data register state is used to shift the selected test data registers by one stage. Shifting is
from MSB to LSB and occurs on the rising edge of TCK.
Update-DR
The update data register state is used to load a test register's parallel output latch. In general, the
output latches are used to control the device. For example, for the EXTEST instruction, the
boundary scan test register's parallel output latches are used to control the device's outputs. The
parallel output latches are updated on the falling edge of TCK.
Capture-IR
The capture instruction register state is used to load the instruction register with a fixed
instruction. The load occurs on the rising edge of TCK.
Shift-IR
The shift instruction register state is used to shift both the instruction register and the selected test
data registers by one stage. Shifting is from MSB to LSB and occurs on the rising edge of TCK.
Update-IR
The update instruction register state is used to load a new instruction into the instruction register.
The new instruction must be scanned in using the Shift-IR state. The load occurs on the falling
edge of TCK.
The Pause-DR and Pause-IR states are provided to allow shifting through the test data and/or
instruction registers to be momentarily paused.
Boundary Scan Instructions
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990267, Issue 3
291
PMC [ PMC-SIERRA, INC ]
