M68HC12A4EVB Freescale Semiconductor, M68HC12A4EVB Datasheet - Page 299

• Manufacturer Part Number: M68HC12A4EVB
• Manufacturer: Freescale Semiconductor

Specifications of M68HC12A4EVB

• Lead Free Status / Rohs Status: Not Compliant

18.3.8 BDM Address Register
The 16-bit ADDRESS register is temporary storage for BDM hardware and firmware commands. The
register can be read in all modes but is not normally accessed by users. It is written only by BDM
hardware.
18.3.9 BDM CCR Holding Register
The CCRSAV register is used to save the state of the condition code register (CCR) of the user’s program
when entering BDM. It is also used for temporary storage in the BDM firmware. The register is initialized
by the firmware to equal the CPU CCR register.
18.4 Breakpoints
Hardware breakpoints are used to debug software on the MCU by comparing actual address and data
values to predetermined data in setup registers. A successful comparison places the CPU in background
debug mode (BDM) or initiates a software interrupt (SWI).
Breakpoint features designed into the MCU include:
Freescale Semiconductor
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Mode selection for BDM or SWI generation
Program fetch tagging for cycle of execution breakpoint
Second address compare in dual address modes
Range compare by disable of low byte address
Data compare in full feature mode for non-tagged breakpoint
Byte masking for high/low byte data compares
R/W compare for non-tagged compares
Tag inhibit on BDM TRACE
Address: $FF04
Address: $FF05
Address: $FF06
Reset:
Reset:
Reset:
Read:
Read:
Read:
Write:
Write:
Write:
CCR7
Bit 7
Bit 7
Bit 7
A15
A7
Figure 18-9. BDM CCR Holding Register (CCRSAV)
0
0
0
Figure 18-8. BDM Address Register (ADDRESS)
CCR6
A14
A6
6
0
6
0
6
0
M68HC12B Family Data Sheet, Rev. 9.1
CCR5
A13
A5
5
0
5
0
5
0
CCR4
A12
A4
4
0
4
0
4
0
CCR3
A11
A3
3
0
3
0
3
0
CCR2
A10
A2
2
0
2
0
2
0
CCR1
A9
A1
1
0
1
0
1
0
CCR0
Bit 0
Bit 0
Bit 0
A8
A0
0
0
0
Breakpoints
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