MC68HC908GR8CDW Freescale Semiconductor, MC68HC908GR8CDW Datasheet - Page 344
MC68HC908GR8CDW
Manufacturer Part Number
MC68HC908GR8CDW
Description
IC MCU 8K FLASH 8MHZ 28-SOIC
Manufacturer
Freescale Semiconductor
Series
HC08r
Datasheet
1.MC68HC908GR4CFAE.pdf
(408 pages)
Specifications of MC68HC908GR8CDW
Core Processor
HC08
Core Size
8-Bit
Speed
8MHz
Connectivity
SCI, SPI
Peripherals
LVD, POR, PWM
Number Of I /o
17
Program Memory Size
7.5KB (7.5K x 8)
Program Memory Type
FLASH
Ram Size
384 x 8
Voltage - Supply (vcc/vdd)
2.7 V ~ 5.5 V
Data Converters
A/D 6x8b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
28-SOIC (7.5mm Width)
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Eeprom Size
-
- Current page: 344 of 408
- Download datasheet (4Mb)
Timer Interface Module (TIM)
22.5.7 Unbuffered PWM Signal Generation
Technical Data
344
NOTE:
increments. Writing $0080 (128) to the TIM channel registers produces
a duty cycle of 128/256 or 50%.
Any output compare channel can generate unbuffered PWM pulses as
described in
because changing the pulse width requires writing the new pulse width
value over the old value currently in the TIM channel registers.
An unsynchronized write to the TIM channel registers to change a pulse
width value could cause incorrect operation for up to two PWM periods.
For example, writing a new value before the counter reaches the old
value but after the counter reaches the new value prevents any compare
during that PWM period. Also, using a TIM overflow interrupt routine to
write a new, smaller pulse width value may cause the compare to be
missed. The TIM may pass the new value before it is written.
Use the following methods to synchronize unbuffered changes in the
PWM pulse width on channel x:
In PWM signal generation, do not program the PWM channel to toggle
on output compare. Toggling on output compare prevents reliable 0%
duty cycle generation and removes the ability of the channel to self-
correct in the event of software error or noise. Toggling on output
compare also can cause incorrect PWM signal generation when
changing the PWM pulse width to a new, much larger value.
Freescale Semiconductor, Inc.
•
•
For More Information On This Product,
When changing to a shorter pulse width, enable channel x output
compare interrupts and write the new value in the output compare
interrupt routine. The output compare interrupt occurs at the end
of the current pulse. The interrupt routine has until the end of the
PWM period to write the new value.
When changing to a longer pulse width, enable TIM overflow
interrupts and write the new value in the TIM overflow interrupt
routine. The TIM overflow interrupt occurs at the end of the current
PWM period. Writing a larger value in an output compare interrupt
routine (at the end of the current pulse) could cause two output
compares to occur in the same PWM period.
Timer Interface Module (TIM)
Go to: www.freescale.com
Pulse Width Modulation
(PWM). The pulses are unbuffered
MC68HC908GR8 — Rev 4.0
MOTOROLA
Related parts for MC68HC908GR8CDW
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet:
Part Number:
Description:
Manufacturer:
Freescale Semiconductor, Inc
Datasheet: