Hitachi F-ZTAT H8/3039 Series Hardware Manual page 250

Examples of PWM Mode: Figure 8-29 shows examples of operation in PWM mode. The PWM
waveform is output from the TIOCA pin. The output goes to 1 at compare match with GRA, and
to 0 at compare match with GRB.
In the examples shown, TCNT is cleared by compare match with GRA or GRB. Synchronized
operation and free-running counting are also possible.
TCNT value
GRA
GRB
H'0000
TIOCA
TCNT value
GRB
GRA
H'0000
TIOCA
240
Counter cleared by compare match with GRA
a. Counter cleared by GRA
Counter cleared by compare match with GRB
b. Counter cleared by GRB
Figure 8-29 PWM Mode (Example 1)
Time
Time