Freescale Semiconductor MC68HC908MR32 Manual Do Utilizador

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MC68HC908MR32 • MC68HC908MR16 Data Sheet, Rev. 6.1
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Freescale Semiconductor
18.2.3.1  Break Status and Control Register
The break status and control register (BRKSCR) contains break module enable and status bits.
BRKE — Break Enable Bit
This read/write bit enables breaks on break address register matches. Clear BRKE by writing a logic 
0 to bit 7. Reset clears the BRKE bit.
1 = Breaks enabled on 16-bit address match
0 = Breaks disabled on 16-bit address match
BRKA — Break Active Bit
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.
1 = When read, break address match
0 = When read, no break address match
18.2.3.2  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:
$FE0E
Bit  7
6
5
4
3
2
1
Bit  0
Read:
BRKE
BRKA
0
0
0
0
0
0
Write:
Reset:
0
0
0
0
0
0
0
0
= Unimplemented
Figure 18-3. Break Status and Control Register (BRKSCR)
Address:
$FE0C
Bit  7
6
5
4
3
2
1
Bit  0
Read:
Bit 15
14
13
12
11
10
9
Bit 8
Write:
Reset:
0
0
0
0
0
0
0
0
Figure 18-4. Break Address Register High (BRKH)
Address:
$FE0D
Bit  7
6
5
4
3
2
1
Bit  0
Read:
Bit  7
6
5
4
3
2
1
Bit  0
Write:
Reset:
0
0
0
0
0
0
0
0
Figure 18-5. Break Address Register Low (BRKL)