HD64F3039F18 Datasheet, PDF (274/710 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8 Family / H8/300H Series

Section 8 16-Bit Integrated Timer Unit (ITU)
Sample Setup Procedure for Reset-Synchronized PWM Mode
Figure 8.31 shows a sample procedure for setting up reset-synchronized PWM mode.
Reset-synchronized PWM mode
Stop counter
1
Select counter clock
2
Select counter clear source
3
Select reset-synchronized
PWM mode
4
Set TCNT
5
Set general registers
6
Start counter
7
Reset-synchronized PWM mode
1. Clear the STR3 bit in TSTR to 0 to
halt TCNT3. Reset-synchronized
PWM mode must be set up while
TCNT3 is halted.
2. Set bits TPSC2 to TPSC0 in TCR to
select the counter clock source for
channel 3. If an external clock source
is selected, select the external clock
edge(s) with bits CKEG1 and CKEG0
in TCR.
3. Set bits CCLR1 and CCLR0 in TCR3
to select GRA3 compare match as
the counter clear source.
4. Set bits CMD1 and CMD0 in TFCR to
select reset-synchronized PWM mode.
TIOCA₃, TIOCB₃, TIOCA₄, TIOCB₄,
TOCXA₄, and TOCXB₄ automatically
become PWM output pins.
5. Preset TCNT3 to H'0000. TCNT4
need not be preset.
6. GRA3 is the waveform period register.
Set the waveform period value in
GRA3. Set transition times of the
PWM output waveforms in GRB3,
GRA4, and GRB4. Set times within
the compare match range of TCNT3.
X ≤ GRA3 (X: setting value)
7. Set the STR3 bit in TSTR to 1 to start
TCNT3.
Figure 8.31 Setup Procedure for Reset-Synchronized PWM Mode (Example)
Rev.3.00 Mar. 26, 2007 Page 250 of 682
REJ09B0353-0300