MC68HC12 Datasheet, PDF (226/478 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
possible to know where the count is with respect to the duty value and
software can be used to make adjustments by turning the enable bit off
and on.
The four PWM channel outputs share general-purpose port P pins.
Enabling PWM pins takes precedence over the general-purpose port.
When PWM are not in use, the port pins may be used for discrete
input/output.
CLOCK SOURCE
(ECLK or Scaled ECLK)
GATE
(CLOCK EDGE SYNC)
PWCNTx
RESET
CENTR = 0
UP/DOWN
8-BIT COMPARE =
PWDTYx
PWENx
SYNC
PPOL = 0
8-BIT COMPARE =
PWPERx
FROM PORT P
DATA REGISTER
S
Q
MUX
Q
R
PPOLx
MUX
TO PIN
DRIVER
PPOL = 1
PWDTY
PWPER
Figure 14-1. Block Diagram of PWM Left-Aligned Output Channel
Technical Data
226
Pulse Width Modulator
MC68HC912DT128A — Rev 4.0
MOTOROLA