MC68HC12 Datasheet, PDF (228/478 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
PSBCK
LIMBDM
ECLK
0:0:0
0:0:1
PSBCK IS BIT 0 OF PWCTL REGISTER.
INTERNAL SIGNAL LIMBDM IS ONE IF THE MCU IS IN BACKGROUND DEBUG MODE.
CLOCK A
0:0:0
÷2
0:0:1
=0
8-BIT DOWN COUNTER
PWSCNT0
0:1:0
÷2
0:1:0
0:1:1
÷2
0:1:1
1:0:0
÷2
1:0:0
1:0:1
÷2
1:0:1
1:1:0
÷2
1:1:0
1:1:1
÷2
1:1:1
8-BIT SCALE REGISTER
PWSCAL0
÷2
CLOCK B
8-BIT DOWN COUNTER ^{= 0}
PWSCNT1
BITS:
PCKB2,
PCKB1,
PCKB0
REGISTER:
PWPRES
BITS:
PCKA2,
PCKA1,
PCKA0
8-BIT SCALE REGISTER
PWSCAL1
÷2
*CLOCK S0 = (CLOCK A)/2, (CLOCK A)/4, (CLOCK A)/6,... (CLOCK A)/512
**CLOCK S1 = (CLOCK B)/2, (CLOCK B)/4, (CLOCK B)/6,... (CLOCK B)/512
Figure 14-3. PWM Clock Sources
CLOCK TO PWM
CHANNEL 0
PCLK0
CLOCK TO PWM
CHANNEL 1
PCLK1
CLOCK TO PWM
CHANNEL 2
PCLK2
CLOCK TO PWM
CHANNEL 3
PCLK3
Technical Data
228
Pulse Width Modulator
MC68HC912DT128A — Rev 4.0
MOTOROLA