mc68hc908ld64 Freescale Semiconductor, Inc, mc68hc908ld64 Datasheet - Page 173

• Manufacturer Part Number: mc68hc908ld64
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

12.4 PWM Registers
12.4.1 PWM Data Registers 0 to 7 (0PWM–7PWM)
MC68HC908LD64
Freescale Semiconductor
—
Rev. 3.0
Address:
The PWM module uses of nine registers for data and control functions.
The output waveform of the eight PWM channels are each configured by
an 8-bit register, which contains a 5-bit PWM in MSB portion and a 3-bit
binary rate multiplier (BRM) in LSB portion
xPWM4–xPWM0 — PWM Bits
xBRM2–xBRM0 — Binary Rate Multiplier Bits
Reset:
Read:
Write:
•
•
The value programmed in the 5-bit PWM portion will determine the
pulse length of the output. The clock to the 5-bit PWM portion is the
system bus clock, the repetition rate of the output is hence f
Examples of PWM output waveforms are shown in
The 3-bit BRM will generate a number of narrow pulses which are
equally distributed among an 8-PWM-cycle frame. The number of
pulses generated is equal to the number programmed in the 3-bit
BRM portion. Examples of PWM output waveforms are shown in
Figure
Figure 12-2. PWM Data Registers 0 to 7 (0PWM–7PWM)
PWM data registers ($0070–$0077)
PWM control register ($0078)
xPWM4
$0070–$0077
Bit 7
0
12-4.
Pulse Width Modulator (PWM)
xPWM3
6
0
xPWM2
5
0
xPWM1
4
0
xPWM0
3
0
Pulse Width Modulator (PWM)
xBRM2
2
0
Figure
xBRM1
PWM Registers
1
0
12-4.
Data Sheet
OP
xBRM0
÷ 32.
Bit 0
0
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