mc68hc908gr8vp Freescale Semiconductor, Inc, mc68hc908gr8vp Datasheet - Page 240

• Manufacturer Part Number: mc68hc908gr8vp
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Timer Interface Module (TIM)
22.9.2 TIM Counter Registers
The two read-only TIM counter registers contain the high and low bytes of the value in the TIM counter.
Reading the high byte (TCNTH) latches the contents of the low byte (TCNTL) into a buffer. Subsequent
reads of TCNTH do not affect the latched TCNTL value until TCNTL is read. Reset clears the TIM counter
registers. Setting the TIM reset bit (TRST) also clears the TIM counter registers.
240
Address:
Address:
If you read TCNTH during a break interrupt, be sure to unlatch TCNTL by
reading TCNTL before exiting the break interrupt. Otherwise, TCNTL
retains the value latched during the break.
Reset:
Reset:
Read:
Read:
Write:
Write:
T1CNTH, $0021 and T2CNTH, $002C
T1CNTL, $0022 and T2CNTL, $002D
PS2–PS0
Bit 15
Bit 7
Bit 7
Bit 7
0
0
Figure 22-5. TIM Counter Registers High (TCNTH)
000
001
010
011
100
101
110
111
Figure 22-6. TIM Counter Registers Low (TCNTL)
MC68HC908GR8 • MC68HC908GR4 Data Sheet, Rev. 7
= Unimplemented
= Unimplemented
14
6
0
6
6
0
Table 22-2. Prescaler Selection
13
5
0
5
5
0
NOTE
12
4
0
4
4
0
Internal bus clock ÷ 16
Internal bus clock ÷ 32
Internal bus clock ÷ 64
Internal bus clock ÷ 4
Internal bus clock ÷ 2
Internal bus clock ÷ 8
Internal bus clock ÷1
TIM Clock Source
Not available
11
3
0
3
3
0
10
2
0
2
2
0
1
9
0
1
1
0
Freescale Semiconductor
Bit 0
Bit 8
Bit 0
Bit 0
0
0