MC68HC708XL36 FREESCALE [Freescale Semiconductor, Inc], MC68HC708XL36 Datasheet - Page 179

• Manufacturer Part Number: MC68HC708XL36
• Description: HCMOS Microcontroller Unit
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Pulse Width
Modulation
9-tim4_b
MOTOROLA
NOTE:
to the TIM channel 3 registers enables the TIM channel 3 registers to
synchronously control the output after the TIM overflows. At each
subsequent overflow, the TIM channel registers (2 or 3) that control the
output are the ones written to last. TSC2 controls and monitors the
buffered output compare function, and TIM channel 3 status and control
register (TSC3) is unused. While the MS2B bit is set, the channel 3 pin,
TCH3, is available as a general-purpose I/O pin.
In buffered output compare operation, do not write new output compare
values to the currently active channel registers. Writing to the active
channel registers is the same as generating unbuffered output
compares.
By using the toggle-on-overflow feature with an output compare
channel, the TIM can generate a PWM signal. The value in the TIM
counter modulo registers determines the period of the PWM signal. The
channel pin toggles when the counter reaches the value in the TIM
counter modulo registers. The time between overflows is the period of
the PWM signal.
As
registers determines the pulse width of the PWM signal. The time
between overflow and output compare is the pulse width. Program the
TIM to clear the channel pin on output compare if the state of the PWM
pulse is logic 1. Program the TIM to set the pin if the state of the PWM
pulse is logic 0.
Freescale Semiconductor, Inc.
Figure 3
For More Information On This Product,
TCHx
OVERFLOW
Go to: www.freescale.com
shows, the output compare value in the TIM channel
Figure 3. PWM Period and Pulse Width
PULSE
WIDTH
PERIOD
TIM
COMPARE
OUTPUT
OVERFLOW
COMPARE
OUTPUT
OVERFLOW
Functional Description
MC68HC708XL36
COMPARE
OUTPUT
TIM
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