B.4. Public instructions

Instructions are loaded into the TAP state machine by scanning the appropriate bit pattern for the instruction when the TAP controller is in the SHIFT-IR state, and then advancing the TAP controller through the UPDATE-IR state.

Table B.1 shows the public instructions.

Table B.1. Public instructions

Instruction

Value

EXTEST

b0000

SAMPLE/PRELOAD

b0011

SCAN_N

b0010

INTEST

b1100

IDCODE

b1110

BYPASS

b1111

RESTART

b0100

In the following descriptions, the ARM7EJ-S processor samples DBGTDI and DBGTMS on the rising edge of CLK with DBGTCKEN HIGH. All output transitions on DBGTDO occur as a result of the rising edge of CLK with DBGTCKEN HIGH.

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