XC912BC32CFU8 Motorola Semiconductor Products, XC912BC32CFU8 Datasheet - Page 324

• Manufacturer Part Number: XC912BC32CFU8
• Description: M68HC12B Family Data Sheet
• Manufacturer: Motorola Semiconductor Products

Development Support
18.3.5.2 Firmware Command
Data Sheet
324
The bits in the BDM instruction register have these meanings when a firmware
command is executed.
H/F — Hardware/Firmware Flag
DATA — Data Flag
R/W — Read/Write Flag
TTAGO — Trace, Tag, Go Field
REGN — Register/Next Field
Indicates which register is being affected by a command. In the case of a
READ_NEXT or WRITE_NEXT command, index register X is pre-incremented
by two and the word pointed to by X is then read or written.
Address: $FF00
Reset:
Read:
Write:
0 = Firmware control logic
1 = Hardware control logic
0 = No data
1 = Data included in command
0 = Write
1 = Read
Figure 18-5. BDM Instruction Register (INSTRUCTION)
Bit 7
H/F
0
TTAGO Value
TTAGO Value
Development Support
DATA
6
0
000
001
010
011
00
01
10
11
Table 18-5. TTAGO Decoding
Table 18-6. REGN Decoding
R/W
5
0
4
0
TTAGO
READ/WRITE NEXT
3
0
Instruction
Instruction
TRACE1
TAGGO
GO
PC
—
—
—
M68HC12B Family — Rev. 8.0
2
0
REGN
1
0
MOTOROLA
Bit 0
0