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CHAPTER 9 TIMER/COUNTER FUNCTION
375
User’s Manual U15195EJ5V0UD
(2/2)
Bit position
Bit name
Function
Selects the internal count clock for TM3.
CS2 CS1 CS0
Count
clock
0 0 0
f
CLK
/2
0 0 1
f
CLK
/4
0 1 0
f
CLK
/8
0 1 1
f
CLK
/16
1 0 0
f
CLK
/32
1 0 1
f
CLK
/64
1 1 0
f
CLK
/128
1 1 1
f
CLK
/256
6 to 4
CS2 to CS0
Caution Do not change the CS2 to CS0 bits during timer operation. If they
are to be changed, they must be changed after setting the TM3CE bit
to 0. If the CS2 to CS0 bits are overwritten during timer operation,
the operation is not guaranteed.
Remark
f
CLK
: Base clock
1
TM3CE
Controls the operation of TM3.
0: Count disabled (timer stopped at 0000H and does not operate)
1: Count operation performed.
Caution
If TM3CE = 0, the external pulse output (TO3) becomes inactive level
(The active level of TO3 output is set with the ALV bit of the TMC31
register).
0
TM3CAE
Controls the internal count clock.
0: Entire TM3 unit asynchronously reset. Stop base clock supply to TM3 unit.
1: Base clock (f
CLK
) supplied to TM3 unit.
Cautions 1. When TM3CAE = 0 is set, the TM3 unit can be reset
asynchronously.
2. When TM3CAE = 0, the TM3 unit is in a reset state. To operate
TM3, first set TM3CAE = 1.
3. When the TM3CAE bit is changed from 1 to 0, all the registers of
the TM3 unit are initialized. When again setting TM3CAE = 1, be
sure to then again set all the registers of the TM3 unit.