Hitachi H8/3022 Hardware Manual page 249

Figure 8-30 shows examples of the output of PWM waveforms with duty cycles of 0% and 100%.
If the counter is cleared by compare match with GRB, and GRA is set to a higher value than GRB,
the duty cycle is 0%. If the counter is cleared by compare match with GRA, and GRB is set to a
higher value than GRA, the duty cycle is 100%.
TCNT value
GRB
GRA
H'0000
TIOCA
TCNT value
GRA
GRB
H'0000
TIOCA
Counter cleared by compare match with GRB
Write to GRA
a. 0% duty cycle
Counter cleared by compare match with GRA
Write to GRB
b. 100% duty cycle
Figure 8-30 PWM Mode (Example 2)
Write to GRA
Write to GRB
Time
Time
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