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Background Debug Mode (BDM) Interface
MCF5253 Reference Manual, Rev. 1
Freescale Semiconductor
20-21
Operand Data:
A single operand is data to be written to the memory location. Byte data is transmitted as a 16-bit word,
justified in the least significant byte; 16- and 32-bit operands are transmitted as 16 and 32 bits, respectively.
Result Data:
Command complete status is indicated by returning the data $FFFF (with the status bit cleared) when the
register write is complete. A value of $0001 (with the status bit set) is returned if a bus error occurs.
20.3.4.1.7
Resume Execution (GO)
The GO command flushes and refills the pipeline before resuming normal instruction execution.
Prefetching begins at the current PC and current privilege level. If any register (For example, the PC or
SR) was altered by a BDM command while halted, the updated value is used as the prefetching resumes.
Command Formats:
Command Sequence:
Figure 20-18. Resume Execution
Operand Data:
None
Result Data:
The “command complete” response ($0FFFF) is returned during the next shift operation.
20.3.4.1.8
No Operation (NOP)
NOP performs no operation and may be used as a null command where required.
Command Formats:
Command Sequence:
Figure 20-19. No Operation Command Sequence
Table 20-12. GO Command
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
$0
$C
$0
$0
Table 20-13. NOP Command
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
$0
$0
$0
$0
SYNC_PC
GO
???
NEXT CMD
“CMD COMPLETE”
SYNC_PC
NOP
???
NEXT CMD
“CMD COMPLETE”
Summary of Contents for MCF5253
Page 1: ...Document Number MCF5253RM Rev 1 08 2008 MCF5253 Reference Manual...
Page 26: ...MCF5253 Reference Manual Rev 1 xxvi Freescale Semiconductor...
Page 32: ...MCF5253 Reference Manual Rev 1 xxxii Freescale Semiconductor...
Page 46: ...MCF5253 Introduction MCF5253 Reference Manual Rev 1 1 14 Freescale Semiconductor...
Page 62: ...Signal Description MCF5253 Reference Manual Rev 1 2 16 Freescale Semiconductor...
Page 98: ...Instruction Cache MCF5253 Reference Manual Rev 1 5 10 Freescale Semiconductor...
Page 104: ...Static RAM SRAM MCF5253 Reference Manual Rev 1 6 6 Freescale Semiconductor...
Page 128: ...Synchronous DRAM Controller Module MCF5253 Reference Manual Rev 1 7 24 Freescale Semiconductor...
Page 144: ...Bus Operation MCF5253 Reference Manual Rev 1 8 16 Freescale Semiconductor...
Page 176: ...System Integration Module SIM MCF5253 Reference Manual Rev 1 9 32 Freescale Semiconductor...
Page 198: ...Analog to Digital Converter ADC MCF5253 Reference Manual Rev 1 12 6 Freescale Semiconductor...
Page 246: ...DMA Controller MCF5253 Reference Manual Rev 1 14 18 Freescale Semiconductor...
Page 282: ...UART Modules MCF5253 Reference Manual Rev 1 15 36 Freescale Semiconductor...
Page 344: ...Audio Interface Module AIM MCF5253 Reference Manual Rev 1 17 46 Freescale Semiconductor...
Page 362: ...I2 C Modules MCF5253 Reference Manual Rev 1 18 18 Freescale Semiconductor...
Page 370: ...Boot ROM MCF5253 Reference Manual Rev 1 19 8 Freescale Semiconductor...