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❍ External trigger operation
The counter is started if a valid edge (rising, falling, or both edges can be selected) is input to
the TIN pin.
Figure 14.4-5 shows the external trigger operation in reload mode.
Figure 14.4-5 Count operation in reload mode (external trigger operation)
Count clock
Counter
Data load signal
UF bit
CNTE bit
TIN pin
TOT pin 2T to 2.5T
T : Machine cycle * : The time from trigger input to loading the reload data is 1T.
Note:
The trigger pulse width input to the TIN pin shall be 2T (T: machine cycle) or more.
❍ External gate input operation
Counting starts when the software trigger bit (TRG) is set to "1" while the timer counter enable
bit (CNTE) of the timer control status register (TMCSR) is set to "1".
Counting starts when a valid level ("L" level or "H" level can be selected) of gate input specified
in the operation mode setting bits(MOD2, MOD1, and MOD0) is input to the TIN pins.
Figure 14.4-6 Count operation in reload mode (external gate input operation)
Internal count clock
Counter
Data load signal
UF bit
CNTE bit
TRG bit
TIN pin
TOT pin
* : It takes 1T from trigger input to loading reload data.
Note:
The trigger pulse width input to the TIN pin shall be 2T (T: machine cycle) or more.
Reload
Reload
-1
0000
H
data
data
*
Reload data
-1
-1
1 machine cycle*
CHAPTER 14 16-BIT RELOAD TIMER
Reload
-1
0000
-1
H
data
Reload
-1
0000
-1
-1
H
data
Reload
0000
-1
H
data
307
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