MC68HC908GR8 Datasheet, PDF (226/286 Pages) Freescale Semiconductor, Inc – M68HC08 Microcontrollers

Timebase Module (TBM)
CGMXCLK
÷2 ÷2 ÷2
÷2
÷2
÷2
÷2
TBON
TBMINT
÷2 ÷2 ÷2 ÷2
÷2 ÷2
÷2 ÷2
000
001
010
011
100
101
110
111
Figure 21-1. Timebase Block Diagram
TBIF
TBIE
R
21.5 Low-Power Modes
The WAIT and STOP instructions put the MCU in low power-consumption standby modes.
21.5.1 Wait Mode
The timebase module remains active after execution of the WAIT instruction. In wait mode, the timebase
register is not accessible by the CPU.
If the timebase functions are not required during wait mode, reduce the power consumption by stopping
the timebase before enabling the WAIT instruction.
21.5.2 Stop Mode
The timebase module may remain active after execution of the STOP instruction if the oscillator has been
enabled to operate during stop mode through the OSCSTOPEN bit in the CONFIG register. The timebase
module can be used in this mode to generate a periodic wakeup from stop mode.
If the oscillator has not been enabled to operate in stop mode, the timebase module will not be active
during STOP mode. In stop mode, the timebase register is not accessible by the CPU.
MC68HC908GR8 • MC68HC908GR4 Data Sheet, Rev. 7
226
Freescale Semiconductor