MC68HC908GZ8 FREESCALE [Freescale Semiconductor, Inc], MC68HC908GZ8 Datasheet - Page 253

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

As an example, a clock source of 4.9152 MHz, with the TMCLKSEL set for divide-by-128 and the
TBR2–TBR0 set to {011}, the divider tap is1 and the interrupt rate calculates to:
18.6 Low-Power Modes
The WAIT and STOP instructions put the MCU in low power- consumption standby modes.
18.6.1 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 executing the WAIT instruction.
18.6.2 Stop Mode
The timebase module may remain active after execution of the STOP instruction if the internal clock
generator has been enabled to operate during stop mode through the OSCENINSTOP bit in the
configuration register. The timebase module can be used in this mode to generate a periodic wakeup from
stop mode.
If the internal clock generator 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.
If the timebase functions are not required during stop mode, reduce power consumption by disabling the
timebase module before executing the STOP instruction.
Freescale Semiconductor
1/(4.9152 x 10
Do not change TBR2–TBR0 bits while the timebase is enabled
(TBON = 1).
6
/128) = 26 μs
TBR2
0
0
0
0
1
1
1
1
MC68HC908GZ16 • MC68HC908GZ8 Data Sheet, Rev. 4
Table 18-1. Timebase Divider Selection
TBR1
0
0
1
1
0
0
1
1
TBR0
0
1
0
1
0
1
0
1
NOTE
32,768
8192
2048
128
64
32
16
0
8
TMBCLKSEL
Divider Tap
4,194,304
1,048,576
262144
16,384
8192
4096
2048
1024
1
Low-Power Modes
253