hd64338342hw Renesas Electronics Corporation., hd64338342hw Datasheet - Page 451

• Manufacturer Part Number: hd64338342hw
• Description: Renesas 8-bit Single-chip Microcomputer H8 Family/h8/300l Super Low Power Series
• Manufacturer: Renesas Electronics Corporation.

11.3
11.3.1
When using the 14-bit PWM, set the registers in the following sequence.
1. Set bit PWM in port mode register 3 (PMR3) to 1 so that pin P3
2. Set bits PWCR1 and PWCR0 in the PWM control register (PWCR) to select a conversion
3. Set the output waveform data in PWM data registers U and L (PWDRU/L). Be sure to write in
One conversion period consists of 64 pulses, as shown in figure 11.2. The total of the high-level
pulse widths during this period (T
relation can be represented as follows.
where t is the PWM input clock period: 2/ (PWCR = H'0), 4/ (PWCR = H'1), 8/ (PWCR =
H'2), or 16/ (PWCR = H'3).
Example: Settings in order to obtain a conversion period of 32,768 µs:
output.
period of 131,072/ (PWCR1 = 1, PWCR0 = 1), 65,536/ (PWCR1 = 1, PWCR0 = 0),
32,768/ (PWCR1 = 0, PWCR0 = 1), or 16,384/ (PWCR1 = 0, PWCR0 = 0).
the correct sequence, first PWDRL then PWDRU. When data is written to PWDRU, the data
in these registers will be latched in the PWM waveform generator, updating the PWM
waveform generation in synchronization with internal signals.
Operation
Operation
T
When PWCR1 = 0 and PWCR0 = 0, the conversion period is 16,384/ , so must be 0.5
MHz. In this case, tfn = 512 µs, with 1/ (resolution) = 2.0 µs.
When PWCR1 = 0 and PWCR0 = 1, the conversion period is 32,768/ , so must be 1
MHz. In this case, tfn = 512 µs, with 2/ (resolution) = 2.0 µs.
When PWCR1 = 1 and PWCR0 = 0, the conversion period is 65,536/ , so must be 2
MHz. In this case, tfn = 512 µs, with 4/ (resolution) = 2.0 µs.
Accordingly, for a conversion period of 32,768 µs, the system clock frequency ( ) must
be 0.5 MHz, 1 MHz, or 2 MHz.
H
= (data value in PWDRU and PWDRL + 64)
H
) corresponds to the data in PWDRU and PWDRL. This
Rev. 6.00 Aug 04, 2006 page 415 of 680
t /2
0
/PWM is designated for PWM
Section 11 14-Bit PWM
REJ09B0145-0600