MC68HC908QL4 Datasheet, PDF (191/226 Pages) Motorola, Inc – Microcontrollers

Break Module (BRK)
16.2.2.3 Break Auxiliary Register
The break auxiliary register (BRKAR) contains a bit that enables software to disable the COP while the
MCU is in a state of break interrupt with monitor mode.
Bit 7
6
5
4
3
2
1
Bit 0
Read: 0
0
0
0
0
0
0
BDCOP
Write:
Reset: 0
0
0
0
0
0
0
0
= Unimplemented
Figure 16-6. Break Auxiliary Register (BRKAR)
BDCOP — Break Disable COP Bit
This read/write bit disables the COP during a break interrupt. Reset clears the BDCOP bit.
1 = COP disabled during break interrupt
0 = COP enabled during break interrupt
16.2.2.4 Break Status Register
The break status register (BSR) contains a flag to indicate that a break caused an exit from wait mode.
This register is only used in emulation mode.
Bit 7
6
5
Read:
R
R
R
Write:
Reset:
R = Reserved
4
3
2
1
Bit 0
SBSW
R
R
R
Note⁽¹⁾
R
0
1. Writing a 0 clears SBSW.
Figure 16-7. Break Status Register (BSR)
SBSW — SIM Break Stop/Wait
SBSW can be read within the break state SWI routine. The user can modify the return address on the
stack by subtracting one from it.
1 = Wait mode was exited by break interrupt
0 = Wait mode was not exited by break interrupt
16.2.2.5 Break Flag Control Register
The break control register (BFCR) contains a bit that enables software to clear status bits while the MCU
is in a break state.
Bit 7
6
5
4
3
2
1
Bit 0
Read:
BCFE
R
R
R
R
R
R
R
Write:
Reset: 0
R = Reserved
Figure 16-8. Break Flag Control Register (BFCR)
BCFE — Break Clear Flag Enable Bit
This read/write bit enables software to clear status bits by accessing status registers while the MCU is
in a break state. To clear status bits during the break state, the BCFE bit must be set.
1 = Status bits clearable during break
0 = Status bits not clearable during break
MC68HC908QL4 Data Sheet, Rev. 7
Freescale Semiconductor
191