Mitsubishi Electric M32R Series User Manual page 770

19
19.4.2 IR Path Sequence
Instruction code is set in the Instruction Register (JTAGIR) to select the data register to be
accessed in the subsequent DR path sequence. The IR path sequence is performed following the
procedure described below.
(1) Enter JTMS = high for a period of two JTCK cycles from "Run-Test/Idle" state to go to
"Select-IR-Scan" state.
(2) Set JTMS = low to go to "Capture-IR" state. At this time, b'110001 (fixed value) is set in the
instruction register's shift register stage.
(3) Subsequently, enter JTMS = low to go to "Shift-IR" state. In "Shift-IR" state, the value of the
shift register stage is shifted right one bit every cycle, and the data b'110001 (fixed value)
that was set in (2) is serially output from the JTDO pin. At the same time, the instruction code
serially entered from the JTDI pin is set in the shift register stage bit by bit. Because
instruction code is set in the instruction register which is comprised of 6 bits, the "Shift-IR"
state continues for a period of 6 JTCK cycles. To stop the shift operation in the middle, go to
"Pause-IR" state via temporarily "Exit1-IR" state (by setting JTMS input from high to low).
Also, to return from "Pause-IR" state, go to "Shift-IR" state via temporarily "Exit1-IR" state
(by setting JTMS input from high to low).
(4) By setting JTMS = high, go from "Shift-IR" state to "Exit1-IR" state. This completes the shift
operation.
(5) Subsequently, enter JTMS = high to go to "Update-IR" state. In "Update-IR" state, the
instruction code that was set in the instruction register's shift register stage is transferred to
the instruction register's parallel output stage and, thus, JTAG instruction decoding begins.
(6) Subsequently, enter JTMS = high to go to "Select-DR-Scan" state or JTMS = low to go to
"Run-Test/Idle" state.
19-8
19.4 Basic Operation of JTAG
JTAG
Ver.0.10