AN2104 Freescale Semiconductor, AN2104 Datasheet - Page 5

• Manufacturer Part Number: AN2104
• Description: Using Background Debug Mode
• Manufacturer: Freescale Semiconductor

AN2104
To execute firmware commands, the user must have the BDM enabled
and active. See
CPU, which executes code out of the BDM ROM.
WRITE_NEXT
READ_NEXT
WRITE_PC
WRITE_SP
Command
Freescale Semiconductor, Inc.
READ_PC
READ_SP
WRITE_D
WRITE_X
WRITE_Y
READ_D
READ_X
READ_Y
TRACE1
TAGGO
For More Information On This Product,
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Opcode (Hex)
Table
Table 2. BDM Firmware Commands
62
63
64
65
66
67
42
43
44
45
46
47
08
10
18
2. When the BDM is active, it has control of the
16-bit data out
16-bit data out Read program counter
16-bit data out Read D accumulator
16-bit data out Read X index register
16-bit data out Read Y index register
16-bit data out Read stack pointer
16-bit data in
16-bit data in
16-bit data in
16-bit data in
16-bit data in
16-bit data in
None
None
None
Data
X = X + 2; Read next word
X = X + 2; Write next word
Write program counter
Write D accumulator
Write X index register
Write Y index register
Write stack pointer
Go to user program
Execute one user instruction
Enable tagging and go to
pointed to by X
pointed to by X
then return to BDM
user program
Description
Theory of Operation
Application Note
5