
Break Module (BRK)
Functional Description
MC68HC908SR12MC68HC08SR12 — Rev. 5.0
Data Sheet
Freescale Semiconductor
Break Module (BRK)
365
Figure 23-1. Break Module Block Diagram
IAB15–IAB8
IAB7–IAB0
8-BIT COMPARATOR
CONTROL
BREAK ADDRESS REGISTER LOW
BREAK ADDRESS REGISTER HIGH
IAB15–IAB0
BREAK
Addr.
Register Name
Bit 7
654321
Bit 0
$FE00
SIM Break Status Register
(SBSR)
Read:
RRRRRR
SBSW
R
Write:
Note
Reset:
0
$FE03
SIM Break Flag Control
Register (SBFCR)
Read:
BCFE
RRRRRRR
Write:
Reset:
0
$FE0C
Break Address Register
High (BRKH)
Read:
Bit 15
14
13
12
11
10
9
Bit 8
Write:
Reset:
00000000
$FE0D
Break Address Register
Low (BRKL)
Read:
Bit 7
654321
Bit 0
Write:
Reset:
00000000
$FE0E
Break Status and Control
Register (BRKSCR)
Read:
BRKE
BRKA
000000
Write:
Reset:
00000000
Note: Writing a logic 0 clears SBSW.
= Unimplemented
R
= Reserved
Figure 23-2. Break Module I/O Register Summary