MC68HC12 Datasheet, PDF (233/478 Pages) Motorola, Inc – The MC68HC912DT128A microcontroller unit (MCU) is a 16-bit device composed of standard on-chip peripherals including a 16-bit central processing unit

Pulse Width Modulator
PWM Register Descriptions
PWPRES — PWM Prescale Counter
$0043
Bit 7
6
5
4
3
2
1
Bit 0
0
Bit 6
5
4
3
2
1
Bit 0
RESET:
0
0
0
0
0
0
0
0
PWPRES is a free-running 7-bit counter. Read anytime. Write only in
special mode (SMOD = 1).
PWSCAL0 — PWM Scale Register 0
$0044
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
RESET:
0
0
0
0
0
0
0
0
Read and write anytime. A write will cause the scaler counter PWSCNT0
to load the PWSCAL0 value unless in special mode with DISCAL = 1 in
the PWTST register.
PWM channels 0 and 1 can select clock S0 (scaled) as its input clock by
setting the control bit PCLK0 and PCLK1 respectively. Clock S0 is
generated by dividing clock A by the value in the PWSCAL0 register + 1
and dividing again by two. When PWSCAL0 = $FF, clock A is divided by
256 then divided by two to generate clock S0.
PWSCNT0 — PWM Scale Counter 0 Value
$0045
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
RESET:
0
0
0
0
0
0
0
0
PWSCNT0 is a down-counter that, upon reaching $00, loads the value
of PWSCAL0. Read any time.
MC68HC912DT128A — Rev 4.0
MOTOROLA
Pulse Width Modulator
Technical Data
233