mc68hc908gr8a Freescale Semiconductor, Inc, mc68hc908gr8a Datasheet - Page 220

• Manufacturer Part Number: mc68hc908gr8a
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Development Support
18.2.2.3 SIM Break Status Register
The SIM break status register (SBSR) contains a flag to indicate that a break caused an exit from wait
mode. This register is only used in emulation mode.
SBSW — SIM Break Stop/Wait
18.2.2.4 SIM Break Flag Control Register
The SIM break control register (SBFCR) contains a bit that enables software to clear status bits while the
MCU is in a break state.
BCFE — Break Clear Flag Enable Bit
18.2.3 Low-Power Modes
The WAIT and STOP instructions put the MCU in low power- consumption standby modes. If enabled,
the break module will remain enabled in wait and stop modes. However, since the internal address bus
does not increment in these modes, a break interrupt will never be triggered.
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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.
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 = Wait mode was exited by break interrupt
0 = Wait mode was not exited by break interrupt
1 = Status bits clearable during break
0 = Status bits not clearable during break
Address: $FE00
Address: $FE03
Reset:
Read:
Reset:
Write:
Read:
Write:
Figure 18-8. SIM Break Flag Control Register (SBFCR)
BCFE
Bit 7
Bit 7
R
R
R
0
Figure 18-7. SIM Break Status Register (SBSR)
MC68HC908GR8A • MC68HC908GR4A Data Sheet, Rev. 5
= Reserved
= Reserved
R
6
R
6
R
5
R
5
R
4
R
4
1. Writing a 0 clears SBSW.
R
3
R
3
R
2
R
2
Note
SBSW
1
0
R
1
(1)
Freescale Semiconductor
Bit 0
Bit 0
R
R