
IEEE 1149.1 Test Access Port (JTAG)
Freescale Semiconductor
37-9
NOTE
External synchronization is required to achieve meaningful results because
there is no internal synchronization between TCLK and the system clock.
37.4.3.4
EXTEST Instruction
The external test (EXTEST) instruction selects the boundary scan register. It forces all output pins and
bidirectional pins configured as outputs to the values preloaded with the SAMPLE/PRELOAD instruction
and held in the boundary scan update registers. EXTEST can also configure the direction of bidirectional
pins and establish high-impedance states on some pins. EXTEST asserts internal reset for the MCU system
logic to force a predictable internal state while performing external boundary scan operations.
37.4.3.5
ENABLE_TEST_CTRL Instruction
The ENABLE_TEST_CTRL instruction selects a 1-bit shift register (TEST_CTRL) for connection as a
shift path between the TDI and TDO pin. When the user transitions the TAP controller to the UPDATE_DR
state, the register transfers its value to a parallel hold register.
37.4.3.6
HIGHZ Instruction
The HIGHZ instruction eliminates the need to backdrive the output pins during circuit-board testing.
HIGHZ turns off all output drivers, including the 2-state drivers, and selects the bypass register. HIGHZ
also asserts internal reset for the MCU system logic to force a predictable internal state.
37.4.3.7
CLAMP Instruction
The CLAMP instruction selects the 1-bit bypass register and asserts internal reset while simultaneously
forcing all output pins and bidirectional pins configured as outputs to the fixed values that are preloaded
and held in the boundary scan update register. CLAMP enhances test efficiency by reducing the overall
shift path to a single bit (the bypass register) while conducting an EXTEST type of instruction through the
boundary scan register.
37.4.3.8
BYPASS Instruction
The BYPASS instruction selects the bypass register, creating a single-bit shift register path from the TDI
pin to the TDO pin. BYPASS enhances test efficiency by reducing the overall shift path when a device
other than the ColdFire processor is the device under test on a board design with multiple chips on the
overall boundary scan chain. The shift register lsb is forced to logic 0 on the rising edge of TCLK after
entry into the capture-DR state. Therefore, the first bit shifted out after selecting the bypass register is
always logic 0. This differentiates parts that support an IDCODE register from parts that support only the
bypass register.
MCF5329 Reference Manual, Rev 3
Содержание MCF5329
Страница 106: ...ColdFire Core 3 32 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 126: ...Enhanced Multiply Accumulate Unit EMAC 4 20 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 148: ...Cache 5 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 154: ...Static RAM SRAM 6 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 184: ...Power Management 8 18 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 204: ...Reset Controller Module 10 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 220: ...System Control Module SCM 11 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 228: ...Crossbar Switch XBS 12 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 268: ...General Purpose I O Module 13 40 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 392: ...SDRAM Controller SDRAMC 18 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 436: ...Fast Ethernet Controller FEC 19 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 564: ...Liquid Crystal Display Controller LCDC 22 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 594: ...FlexCAN 23 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 678: ...Pulse Width Modulation PWM Module 26 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 684: ...Watchdog Timer Module 27 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 692: ...Programmable Interrupt Timers PIT0 PIT3 28 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 704: ...DMA Timers DTIM0 DTIM3 29 12 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 720: ...Queued Serial Peripheral Interface QSPI 30 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 754: ...UART Modules 31 34 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 770: ...I2 C Interface 32 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 790: ...Message Digest Hardware Accelerator MDHA 33 20 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 866: ...Debug Module 36 50 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Страница 902: ...Register Memory Map Quick Reference A 26 Freescale Semiconductor MCF5329 Reference Manual Rev 3...