TIMER A
7.6 Pulse width modulation (PWM) mode
(1 / f
i
)
ꢀ
(216 – 1)
Count source
TAi IN pin’s input signal
Trigger is not generated by this signal.
(1 / fi) ꢀ (n)
PWM pulse output
from TAi OUT pin
Timer Ai interrupt
request bit
f
i
: Frequency of count source
Cleared to “0” when interrupt request is accepted
or cleared by software.
n: Reload register
Note: The above applies when n = “000316” and an external trigger (rising edge of TAi IN pin’s input
signal) is selected.
Fig. 7.6.5 Operation example of 16-bit pulse width modulator
n = Reload register’s contents
(1 / fi
) ꢀ (216 –1)
(1 / f
i
) ꢀ (216 –1)
(1 / fi
) ꢀ (216 –1)
FFFE16
200016
(216 –1) – n
n
000116
Time
Stops
Restarts counting.
counting.
TAi IN pin’s
input signal
ꢀ
PWM pulse
output from
TAi OUT pin
“FFFE16” is set to timer Ai
“000016” is set to timer Ai
“200016” is set to timer Ai
f
i
: Frequency of count source
register.
register.
register.
n: Reload register’s contents
ꢀ
When an arbitrary value is set to the timer Ai register after setting “000016” to it, the timing when the PWM pulse goes “H”
depends on the timing when the new value is set.
Note: The above applies when an external trigger (rising edge of TAi IN pin’s input signal) is selected.
Fig. 7.6.6 Operation example of 16-bit pulse width modulator (when counter value is updated during
pulse output)
7905 Group User’s Manual Rev.1.0
7-45
RENESAS [ RENESAS TECHNOLOGY CORP ]
