mc68hc908gr8b Freescale Semiconductor, Inc, mc68hc908gr8b Datasheet - Page 195

• Manufacturer Part Number: mc68hc908gr8b
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

If the timebase functions are not required during stop mode, reduce power consumption by disabling the
timebase module before executing the STOP instruction.
16.6 Timebase Control Register
The timebase has one register, the timebase control register (TBCR), which is used to enable the
timebase interrupts and set the rate.
TBIF — Timebase Interrupt Flag
TBR2–TBR0 — Timebase Divider Selection Bits
TACK— Timebase Acknowledge Bit
Freescale Semiconductor
This read-only flag bit is set when the timebase counter has rolled over.
These read/write bits select the tap in the counter to be used for timebase interrupts as shown in
Table
The TACK bit is a write-only bit and always reads as 0. Writing a 1 to this bit clears TBIF, the timebase
interrupt flag bit. Writing a 0 to this bit has no effect.
1 = Timebase interrupt pending
0 = Timebase interrupt not pending
1 = Clear timebase interrupt flag
0 = No effect
16-1.
Address: $001C
Do not change TBR2–TBR0 bits while the timebase is enabled (TBON = 1).
Reset:
Read:
Write:
Bit 7
TBIF
0
Figure 16-2. Timebase Control Register (TBCR)
= Unimplemented
Table 16-1. Timebase Divider Selection
TBR2
6
0
TBR2
0
0
0
0
1
1
1
1
MC68HC908GR8B Data Sheet, Rev. 3.0
TBR1
5
0
TBR1
0
0
1
1
0
0
1
1
NOTE
TBR0
4
0
TBR0
0
1
0
1
0
1
0
1
TACK
3
R
0
0
Divider
32,768
= Reserved
8192
2048
128
64
32
16
8
TBIE
2
0
TBON
1
0
Timebase Control Register
Bit 0
R
0
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