MC96F6432
June 22, 2018 Ver. 2.9 161
Figure 11.36 Example of PWM at 4 MHz
Figure 11.37 Example of Changing the Period in Absolute Duty Cycle at 4 MHz
Update period & duty register value at once
The period and duty of PWM comes to move from temporary registers to T4PPRH/L (PWM Period Register) and
T4ADRH/L/T4BDRH/L/T4CDRH/L (PWM Duty Register) when always period match occurs. If you want that the
period and duty is immediately changed, the UPDT bit in the T4PCR1 register must set to ‘1’. It should be noted
that it needs the 3 cycle of timer clock for data transfer in the internal clock synchronization circuit. So the update
data is written before 3 cycle of timer clock to get the right output waveform.
T4CR = 03
H
(2us)
T4PPRH = 00
H
T4PPRL = 0E
H
T4ADRH = 00
H
T4ADRL = 05
H
Duty Cycle
(1+05
H
)X2us = 12us
Duty Cycle
(1+05
H
)X2us = 12us
Duty Cycle
(1+05
H
)X2us = 12us
Period Cycle
(1+0E
H
)X2us = 32us ïƒ 31.25kHz
Period Cycle
(1+0A
H
)X2us = 22us ïƒ 45.5kHz
Duty Cycle(1+80
H
)X250ns = 32.25us
Period Cycle(1+3FF
H
)X250ns = 256us ïƒ 3.9kHz
T4CR = 00
H
(f
XIN
)
T4PPRH = 03
H
T4PPRL = FF
H
T4ADRH = 00
H
T4ADRL = 80
H