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Debug Support
MCF5272 ColdFire
®
Integrated Microprocessor User’s Manual, Rev. 3
Freescale Semiconductor
5-33
5.5.3.3.12
Write Debug Module Register (
WDMREG
)
The operand (longword) data is written to the specified debug module register. All 32 bits of the register
are altered by the write. DSCLK must be inactive while the debug module register writes from the CPU
accesses are performed using the WDEBUG instruction.
Command Format:
shows the definition of the DRc write encoding.
Command Sequence:
Figure 5-40.
WDMREG
Command Sequence
Operand Data:
Longword data is written into the specified debug register. The data is supplied
most-significant word first.
Result Data:
Command complete status (0xFFFF) is returned when register write is complete.
5.6
Real-Time Debug Support
The ColdFire Family provides support debugging real-time applications. For these types of embedded
systems, the processor must continue to operate during debug. The foundation of this area of debug support
is that while the processor cannot be halted to allow debugging, the system can generally tolerate small
intrusions into the real-time operation.
The debug module provides three types of breakpoints—PC with mask, operand address range, and data
with mask. These breakpoints can be configured into one- or two-level triggers with the exact trigger
response also programmable. The debug module programming model can be written from either the
external development system using the debug serial interface or from the processor’s supervisor
programming model using the WDEBUG instruction. Only CSR is readable using the external
development system.
Figure 5-39.
WDMREG
BDM Command Format
15
12
11
8
7
5
4
0
0x2
0xC
100
DRc
D[31:16]
D[15:0]
MS DATA
"NOT READY"
XXX
"ILLEGAL"
LS DATA
"NOT READY"
NEXT CMD
"NOT READY"
WDMREG
???
NEXT CMD
"CMD COMPLETE"