Fujitsu MB90460 Series Hardware Manual page 478

Table 16.6-6 Measurement Mode Operation (2/2)
Measurement mode MOD2 MOD1 MOD0
Falling edge-to-falling
edge period
measurement
All edge pulse-width
measurement
Division
measurement
W: Pulse width being measured
In all modes, the timer does not start count during the period from the start of measurement to input of
measurement start edge. After the measurement start edge is input, the timer is cleared to "0000
count is incremented at each count clock until the measurement termination edge is input.
When the measurement termination edge is input, the following operations are executed
(1) The count end flag (EDIR) of PWCSH0/PWCSH1 is set.
(2) The timer stops count operation (except if the timer is restarted at the same time or
continuous measurement mode of the H/L pulse-width measurement is used).
(3)Continuous measurement mode: The timer value (measurement result) is transferred to PWC0/PWC1.
(4) Single measurement mode: Measurement is terminated (except if the timer is restarted at
the same time).
If all edge-to-edge pulse-width measurement, period measurement, falling edge-to-falling edge period
measurement, or rising edge-to-rising edge period measurement is done in continuous measurement mode,
the termination edge becomes the next measurement start edge.
1 1 1
The falling edge-to-falling edge time is measured.
Start of measurement:
Termination of measurement:
0 1 0
The width between continuous input edges is measured.
Start of measurement:
Termination of measurement:
0 1 1
(Divided by 4 in the above example.)
The input pulse is divided by the division rate set in the division rate
register (DIVR), and the measurement period is obtained as a result.
Start of measurement:
Termination of measurement:
Measurement operation
w w w
Start of Termination of
measurement measurement
Start
w w w
Start of
Termination of
measurement
measurement
Start
φ
w w w
Start of Termination of
measurement measurement
Start
CHAPTER 16 PWC Timer
w
Termination
Start Termination
When the falling edge is detected
When the falling edge is detected
w
Termination
Start
Termination
When the edge is detected
When the edge is detected
w
Termination
The falling edge is detected after
the operation is started.
One period of division signal ends.
H
", and the
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