Exit2-Ir State; Update-Ir State - Intel PXA27 Series Design Manual

JTAG Debug
26.4.5.15

Exit2-IR State

Exit2-IR is a temporary state. If TMS is held high on the rising edge of TCK, the controller enters
the Update-IR state, which terminates the scanning process. If TMS is held low on the rising edge
of TCK, the controller enters the Shift-IR state.
The test data register selected by the current instruction retains its previous value during this state.
The current instruction does not change and the instruction register retains its state.
26.4.5.16

Update-IR State

The instruction shifted into the instruction register is latched onto the parallel output from the shift
register path on the falling edge of TCK. After the instruction is latched, it becomes the current
instruction. The test data register selected by the current instruction retains its previous value.
If TMS is held high on the rising edge of TCK, the controller enters the Select-DR-Scan state. If
TMS is held low on the rising edge of TCK, the controller enters the Run-Test/Idle state.
II:26-14
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Intel PXA27x Processor Family Design Guide