MC68HC708MP16 Datasheet, PDF (136/398 Pages) Freescale Semiconductor, Inc – Microcontrollers

Pulse Width Modulator for Motor Control (PWMMC)
For edge-aligned mode, a 12-bit up-only counter is used to create the
PWM period. Therefore, the PWM resolution in edge-aligned mode is
one clock (highest resolution is125 ns @ f_op = 8 MHz) as shown in
Figure 9-4. Again, the timer modulus register is used to determine the
maximum count. The PWM period will equal: [(timer modulus) x (PWM
clock period)].
Center-aligned operation versus edge-aligned operation is determined
by the option EDGE. See 5.3 Functional Description.
UP-ONLY COUNTER
MODULUS = 4
PWM = 0
PWM = 1
PWM = 2
PERIOD = 4 x (PWM
CLOCK PERIOD)
PWM = 3
PWM = 4
Figure 9-4. Edge-Aligned PWM (Positive Polarity)
Technical Data
136
MC68HC708MP16 — Rev. 3.1
Pulse Width Modulator for Motor Control (PWMMC) Freescale Semiconductor