mc68hc908gr8vp Freescale Semiconductor, Inc, mc68hc908gr8vp Datasheet - Page 64

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

Break Module (BRK)
6.3.2 CPU During Break Interrupts
The CPU starts a break interrupt by:
The break interrupt begins after completion of the CPU instruction in progress. If the break address
register match occurs on the last cycle of a CPU instruction, the break interrupt begins immediately.
64
Note: Writing a logic 0 clears BW.
Addr.
$FE0A
$FE0B
$FE00
$FE03
$FE09
•
•
Loading the instruction register with the SWI instruction
Loading the program counter with $FFFC and $FFFD ($FEFC and $FEFD in monitor mode)
Break Address Register High
Break Address Register Low
SIM Break Status Register
Break Status and Control
Register Name
SIM Break Flag Control
Register (BRKSCR)
Register (SBFCR)
IAB15–IAB0
(BRKH)
(SBSR)
(BRKL)
Reset:
Reset:
Reset:
Reset:
Reset:
Read:
Read:
Read:
Read:
Read:
Write:
Write:
Write:
Write:
Write:
MC68HC908GR8 • MC68HC908GR4 Data Sheet, Rev. 7
Figure 6-1. Break Module Block Diagram
IAB15–IAB8
IAB7–IAB0
Figure 6-2. I/O Register Summary
BRKE
Bit 7
BCFE
Bit 15
Bit 7
BREAK ADDRESS REGISTER HIGH
BREAK ADDRESS REGISTER LOW
R
0
0
0
0
0
0
8-BIT COMPARATOR
8-BIT COMPARATOR
= Unimplemented
BRKA
14
6
R
R
0
0
0
6
0
0
13
5
R
R
0
0
0
5
0
0
0
12
4
R
R
R
1
1
0
4
0
0
0
CONTROL
= Reserved
11
R
R
3
0
0
0
3
0
0
0
10
R
R
2
0
0
0
2
0
0
0
BREAK
Freescale Semiconductor
NOTE
BW
1
R
0
9
0
1
0
0
0
Bit 0
Bit 8
Bit 0
R
R
0
0
0
0
0
0