MMC2114 MOTOROLA [Motorola, Inc], MMC2114 Datasheet - Page 567

• Manufacturer Part Number: MMC2114
• Description: M CORE Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

22.5 Instruction Shift Register
22.5.1 EXTEST Instruction
MMC2114 • MMC2113 • MMC2112 — Rev. 1.0
MOTOROLA
The top-level TAP module uses a 4-bit Instruction Shift Register with no
parity. This register transfers its value to a parallel hold register and
applies an instruction on the falling edge of TCLK when the TAP state
machine is in the update-IR state. To load the instructions into the shift
portion of the register, place the serial data on the TDI pin prior to each
rising edge of TCLK. The MSB of the instruction shift register is the bit
closest to the TDI pin and the LSB is the bit closest to the TDO pin.
Table 22-1
IR3–IR0. The last three instructions in the table are reserved for
manufacturing purposes only.
Unused opcodes are currently decoded to perform the BYPASS
operation, but Motorola reserves the right to change their decodings in
the future.
The external test instruction (EXTEST) selects the Boundary Scan
Register. The EXTEST instruction forces all output pins and bidirectional
pins configured as outputs to the preloaded fixed values (with the
SAMPLE/PRELOAD instruction) and held in the boundary-scan update
registers. The EXTEST instruction can also configure the direction of
bidirectional pins and establish high-impedance states on some pins.
EXTEST also asserts internal reset for the system logic to force a
predictable internal state while performing external boundary scan
operations.
Freescale Semiconductor, Inc.
For More Information On This Product,
JTAG Test Access Port and OnCE
lists the instructions supported along with their opcodes,
Go to: www.freescale.com
JTAG Test Access Port and OnCE
Instruction Shift Register
Advance Information
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