mc68hc908gr8vp Freescale Semiconductor, Inc, mc68hc908gr8vp Datasheet - Page 66

• Manufacturer Part Number: mc68hc908gr8vp
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Break Module (BRK)
BRKA — Break Active Bit
6.5.2 Break Address Registers
The break address registers (BRKH and BRKL) contain the high and low bytes of the desired breakpoint
address. Reset clears the break address registers.
Address:
6.5.3 Break Status Register
The break status register (SBSR) contains a flag to indicate that a break caused an exit from wait mode.
The flag is useful in applications requiring a return to wait mode after exiting from a break interrupt.
BW — Break Wait Bit
BW can be read within the break interrupt routine. The user can modify the return address on the stack
by subtracting 1 from it.
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This read/write status and control bit is set when a break address match occurs. Writing a logic 1 to
BRKA generates a break interrupt. Clear BRKA by writing a logic 0 to it before exiting the break routine.
Reset clears the BRKA bit.
This read/write bit is set when a break interrupt causes an exit from wait mode. Clear BW by writing a
logic 0 to it. Reset clears BW.
1 = (When read) Break address match
0 = (When read) No break address match
1 = Break interrupt during wait mode
0 = No break interrupt during wait mode
$FE09
Note: Writing a logic 0 clears BW.
Address:
Address:
Reset:
Reset:
Reset:
Read:
Read:
Read:
Write:
Write:
Write:
$FE0A
$FE00
Bit 15
Bit 7
Bit 7
Bit 7
Bit 7
R
0
0
0
0
Figure 6-4. Break Address Register High (BRKH)
Figure 6-5. Break Address Register Low (BRKL)
Figure 6-6. SIM Break Status Register (SBSR)
MC68HC908GR8 • MC68HC908GR4 Data Sheet, Rev. 7
14
R
6
0
6
6
0
6
0
0
13
R
R
5
0
5
5
0
5
0
0
= Reserved
12
R
4
0
4
4
0
4
1
1
11
R
3
0
3
3
0
3
0
0
10
R
2
0
2
2
0
2
0
0
NOTE
BW
1
9
0
1
1
0
1
0
Freescale Semiconductor
Bit 0
Bit 8
Bit 0
Bit 0
Bit 0
R
0
0
0
0