HD6473032F16 Datasheet, PDF (391/847 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

Section 10 16-Bit Integrated Timer Unit (ITU)
Examples of Complementary PWM Mode: Figure 10.35 shows an example of operation in
complementary PWM mode. TCNT3 and TCNT4 operate as up/down-counters, counting down
from compare match between TCNT3 and GRA3 and counting up from the point at which TCNT4
underflows. During each up-and-down counting cycle, PWM waveforms are generated by
compare match with general registers GRB3, GRA4, and GRB4. Since TCNT3 is initially set to a
higher value than TCNT4, compare match events occur in the sequence TCNT3, TCNT4, TCNT4,
TCNT3.
TCNT3 and
TCNT4 values
GRA3
GRB3
GRA4
GRB4
H'0000
TIOCA₃
Down-counting starts at compare
match between TCNT3 and GRA3
TCNT3
TCNT4
Up-counting starts when
TCNT4 underflows
Time
TIOCB₃
TIOCA₄
TOCXA₄
TIOCB₄
TOCXB₄
Figure 10.35 Operation in Complementary PWM Mode (Example 1, OLS3 = OLS4 = 1)
Rev. 3.00 Mar 21, 2006 page 361 of 814
REJ09B0302-0300