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Signal Descriptions
Freescale Semiconductor
2-19
2.3.17
DMA Timer Signals
describes the signals of the four DMA timer modules, where
n
equals 0 – 3.
2.3.18
Debug Support Signals
These signals are used as the interface to the on-chip JTAG controller and the BDM logic. Pin functionality
between JTAG and BDM is dependent upon the JTAG_EN pin.
Table 2-19. DMA Timer Signals
Signal Name
Abbreviation
Function
I/O
DMA Timer
n
Input
DT
n
IN
Can be programmed to cause events in the respective timer. It can
clock the event counter or provide a trigger to the timer value capture
logic.
I
DMA Timer
n
Output
DT
n
OUT
Output from respective timer.
O
Table 2-20. Debug Support Signals
Signal Name
Abbreviation
Function
I/O
JTAG Enable
JTAG_EN
Enables JTAG (asserted) or BDM (negated) operation.
I
JTAG Signals
Test Reset
TRST
Active-low signal used to initialize the JTAG logic asynchronously.
I
Test Clock
TCLK
Used to synchronize the JTAG logic.
I
Test Mode Select
TMS
Used to sequence the JTAG state machine. TMS is sampled on the
rising edge of TCLK.
I
Test Data Input
TDI
Serial input for test instructions and data. TDI is sampled on the rising
edge of TCLK.
I
Test Data Output
TDO
Serial output for test instructions and data. TDO is three-stateable and
actively driven in the shift-IR and shift-DR controller states. TDO
changes on the falling edge of TCLK.
O
BDM Signals
Development Serial
Clock
DSCLK
Clocks the serial communication port to the BDM module during
packet transfers.
I
Breakpoint
BKPT
Used to request a manual breakpoint.
I
Development Serial
Input
DSI
Internally-synchronized signal provides data input for the serial
communication port to the BDM module.
I
Development Serial
Output
DSO
Internally-registered signal provides serial output communication for
BDM module responses.
O
Processor Status Clock PSTCLK
Used by the development system to know when to sample DDATA and
PST signals.
O
Processor Status/
Debug Data
PSTDDATA[7:0] Display captured processor status and captured address/data values.
These outputs change on the negative edge of PSTCLK.
O
Summary of Contents for MCF54455
Page 33: ...xxviii Freescale Semiconductor ...
Page 67: ...Freescale Semiconductor 1 ...
Page 125: ...Freescale Semiconductor 1 ...
Page 145: ...Enhanced Multiply Accumulate Unit EMAC 5 21 Freescale Semiconductor ...
Page 173: ...Cache 6 28 Freescale Semiconductor ...
Page 179: ...Static RAM SRAM 7 6 Freescale Semiconductor ...
Page 207: ...Power Management 9 16 Freescale Semiconductor ...
Page 323: ...Reset Controller Module 13 8 Freescale Semiconductor ...
Page 389: ...Pin Multiplexing and Control 16 44 Freescale Semiconductor ...
Page 575: ...PCI Bus Controller 22 58 Freescale Semiconductor ...
Page 600: ...Advanced Technology Attachment ATA Freescale Semiconductor 23 25 ...
Page 601: ...Freescale Semiconductor 1 ...
Page 842: ...I2 C Interface Freescale Semiconductor 33 16 ...
Page 843: ...Freescale Semiconductor 1 ...
Page 921: ...Revision History A 6 Freescale Semiconductor ...