HD6413003RF Datasheet, PDF (368/715 Pages) Renesas Technology Corp – Microcontroller (MCU)

— General register settings outside the counting range (H'0000 to GRA3)
Waveforms with a duty cycle of 0% or 100% can be output by setting a general register to
a value outside the counting range. When a buffer register is set to a value outside the
counting range, then later restored to a value within the counting range, the counting
direction (up or down) must be the same both times. See figure 10-42.
GRA3
GR
H'0000
Output pin
Output pin
BR
0% duty cycle
100% duty cycle
GR
Write during down-counting
Write during up-counting
Figure 10-42 Changing a General Register Setting by Buffer Transfer (Example 2)
Settings can be made in this way by detecting GRA3 compare match or TCNT4
underflow before writing to the buffer register. They can also be made by using GRA3
compare match to activate the DMAC.
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