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14.2.3
Pulse Period Measurement Mode, Pulse Width Measurement Mode
In pulse period measurement mode and pulse width measurement mode, the timer measures pulse period or
pulse width of the external signal.
Table 14.11 shows specifications in pulse period measurement mode and pulse width measurement mode.
Figure 14.27 shows the TBiMR register (i=0 to 5) in pulse period measurement mode and pulse width
shows a pulse width measurement operation.
Table 14.11
Specifications of Pulse Period Measurement Mode, Pulse Width Measurement Mode
NOTES:
1. Bits CNT3 to CNT0 in the TCSPR register select no division (n = 0) or divide-by-2n (n = 1 to 15).
2. An interrupt request is not generated when a pulse to be measured is input at the first valid edge after the count
starts..
3. To set the MR3 bit to 0 (no overflow), wait for one or more count source cycles to write to the TBiMR register
after the MR3 bit becomes 1, while the TBiS bit is set to 1.
4. A value read from the TBi register is undefined until a pulse to be measured is input at the second valid edge
after the count starts.
Item
Specification
Count sources
Count operations
The timer increments a counter value
The counter value is transferred to the reload register at the valid edge of a
pulse to be measured. It becomes 0000h and the count continues.
Count start condition
The TBiS bit (i = 0 to 5) in the TABSR or TBSR register is set to 1 (count starts)
Count stop condition
The TBiS bit is set to 0 (count stops)
Interrupt request generation timing On the valid edge of a pulse to be measured
(2) When the timer overflow
s(3)The MR3 bit in the TBiMR register is set to 1 (overflow) simultaneously.
TBiIN pin function
Input for a pulse to be measured
Read from timer
The TBi register indicates the contents of the reload register (measurement
Write to timer
The TBi register cannot be written