CHAPTER 6 16-BIT TIMER/EVENT COUNTER 00
Preliminary User’s Manual U16315EJ1V0UD
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(10) Capture operation
<1>
If TI000 valid edge is specified as the count clock, a capture operation by the capture register specified as
the trigger for TI000 is not possible.
<2>
To ensure the reliability of the capture operation, the capture trigger requires a pulse two times longer than
the count clock selected by prescaler mode register 00 (PRM00).
<3>
The capture operation is performed at the falling edge of the count clock. An interrupt request input
(INTTM000/INTTM010), however, is generated at the rise of the next count clock.
(11) Compare operation
<1>
When the 16-bit timer capture/compare register (CR000/CR010) is overwritten during timer operation, a
match interrupt may be generated or a clear operation may not be performed normally if that value is close
to or larger than the timer value.
<2>
A capture operation may not be performed for CR000/CR010 set in compare mode even if a capture trigger
has been input.
(12) Edge detection
<1>
If the TI000 or TI010 pin is high level immediately after system reset and the rising edge or both the rising
and falling edges are specified as the valid edge of the TI000 or TI010 pin to enable the 16-bit timer counter
00 (TM00) operation, a rising edge is detected immediately after the operation is enabled. Be careful
therefore when pulling up the TI000 or TI010 pin. However, the rising edge is not detected at restart after
the operation has been stopped once.
<2>
The sampling clock used to eliminate noise differs when the TI000 valid edge is used as the count clock
and when it is used as a capture trigger. In the former case, the count clock is f
X
, and in the latter case the
count clock is selected by prescaler mode register 00 (PRM00). The capture operation is started only after
a valid edge is detected twice by sampling, thus eliminating noise with a short pulse width.