162
Bit 7: TMA7
Bit 6: TMA6
Bit 5: TMA5
Clock Output
0
0
0
ø/32
(initial value)
1
ø/16
1
0
ø/8
1
ø/4
1
0
0
ø
W
/32
1
ø
W
/16
1
0
ø
W
/8
1
ø
W
/4
Bit 4—Reserved Bit: Bit 4 is reserved; it is always read as 1, and cannot be modified.
Bits 3 to 0—Internal Clock Select (TMA3 to TMA0): Bits 3 to 0 select the clock input to TCA.
The selection is made as follows.
Description
Bit 3:
TMA3
Bit 2:
TMA2
Bit 1:
TMA1
Bit 0:
TMA0
Prescaler and Divider Ratio
or Overflow Period
Function
0
0
0
0
PSS, ø/8192
(initial value)
Interval timer
1
PSS, ø/4096
1
0
PSS, ø/2048
1
PSS, ø/512
1
0
0
PSS, ø/256
1
PSS, ø/128
1
0
PSS, ø/32
1
PSS, ø/8
1
0
0
0
PSW, 1 s
Clock time base
1
PSW, 0.5 s
1
0
PSW, 0.25 s
1
PSW, 0.03125 s
1
0
0
PSW and TCA are reset
1
1
0
1