HD6437020 Datasheet, PDF (281/507 Pages) Hitachi Semiconductor – SuperH™ RISC engine

sequence TCNT3, TCNT4, TCNT4, TCNT3 (in this mode, TCNT3 starts out larger than TCNT4).
Figure 10.35 shows examples of PWM waveforms with 0% and 100% duty cycles (in one phase)
in the complementary PWM mode. In this example, the pin output changes upon GRB3 compare
match, so duty cycles of 0% and 100% can be obtained by setting GRB3 to a value larger than
GRA3. Combining buffer operation with the above operation makes it easy to change the duty
while operating. See section 10.4.8, Buffer Operation, for details.
TCNT3, TCNT4 value
GRA3
GRB3
Down-counting starts at compare match
between TCNT3 and GRA3
TCNT3
GRA4
GRB4
TIOCA3
TCNT4
Time
Up-counting starts at TCNT4 underflow
TIOCB3
TIOCA4
TOCXA4
TIOCB4
TOCXB4
Figure 10.34 Complementary PWM Mode Operation Example 1
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