MC68HC908GZ8 FREESCALE [Freescale Semiconductor, Inc], MC68HC908GZ8 Datasheet - Page 275

• Manufacturer Part Number: MC68HC908GZ8
• Description: M68HC08 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

20.2.2.3 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.
SBSW — SIM Break Stop/Wait
20.2.2.4 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.
BCFE — Break Clear Flag Enable Bit
20.2.3 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.
20.3 Monitor ROM (MON)
This subsection describes the monitor ROM (MON) and the monitor mode entry methods. The monitor
ROM allows complete testing of the microcontroller unit (MCU) through a single-wire interface with a host
Freescale Semiconductor
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:
BCFE
Bit 7
Bit 7
R
R
R
0
Figure 20-7. Break Flag Control Register (BFCR)
MC68HC908GZ16 • MC68HC908GZ8 Data Sheet, Rev. 4
Figure 20-6. Break Status Register (BSR)
= Reserved
= Reserved
R
6
R
6
R
5
R
5
R
4
R
4
1. Writing a logic 0 clears SBSW.
R
3
R
3
R
2
R
2
Note
SBSW
1
0
R
1
(1)
Monitor ROM (MON)
Bit 0
Bit 0
R
R
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