MC9S08GB60 Datasheet, PDF (252/290 Pages) Motorola, Inc – Microcontrollers

Development Support
Bit 7
6
5
4
3
2
1
Bit 0
Read: 0
0
0
0
0
0
0
0
Write:
BDFR¹
Reset: 0
0
0
1
0
0
0
0
= Unimplemented or Reserved
1 _{BDFR is writable only through serial active background mode debug commands, not from user programs.}
Figure 15-6. System Background Debug Force Reset Register (SBDFR)
BDFR — Background Debug Force Reset
A serial active background mode command such as WRITE_BYTE allows an external debug host to
force a target system reset. Writing 1 to this bit forces an MCU reset. This bit cannot be written from
a user program.
15.5.3 DBG Registers and Control Bits
The debug module includes nine bytes of register space for three 16-bit registers and three 8-bit control
and status registers. These registers are located in the high register space of the normal memory map so
they are accessible to normal application programs. These registers are rarely if ever accessed by normal
user application programs with the possible exception of a ROM patching mechanism that uses the
breakpoint logic.
15.5.3.1 Debug Comparator A High Register (DBGCAH)
This register contains compare value bits for the high-order eight bits of comparator A. This register is
forced to $00 at reset and can be read at any time or written at any time unless ARM = 1.
15.5.3.2 Debug Comparator A Low Register (DBGCAL)
This register contains compare value bits for the low-order eight bits of comparator A. This register is
forced to $00 at reset and can be read at any time or written at any time unless ARM = 1.
15.5.3.3 Debug Comparator B High Register (DBGCBH)
This register contains compare value bits for the high-order eight bits of comparator B. This register is
forced to $00 at reset and can be read at any time or written at any time unless ARM = 1.
15.5.3.4 Debug Comparator B Low Register (DBGCBL)
This register contains compare value bits for the low-order eight bits of comparator B. This register is
forced to $00 at reset and can be read at any time or written at any time unless ARM = 1.
MC9S08GB/GT Data Sheet, Rev. 2.3
252
Freescale Semiconductor