MC68HC908JB8JPE Freescale Semiconductor, MC68HC908JB8JPE Datasheet - Page 185

• Manufacturer Part Number: MC68HC908JB8JPE
• Description: IC MCU FLASH 8BIT 8K 20-DIP
• Manufacturer: Freescale Semiconductor
• Series: HC08r

Specifications of MC68HC908JB8JPE

• Core Processor: HC08
• Core Size: 8-Bit
• Speed: 3MHz
• Connectivity: USB
• Peripherals: LVD, POR, PWM
• Number Of I /o: 13
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 20-DIP (0.300", 7.62mm)
• Controller Family/series: HC08
• No. Of I/o's: 13
• Ram Memory Size: 256Byte
• Cpu Speed: 3MHz
• No. Of Timers: 1
• Embedded Interface Type: USB
• Rohs Compliant: Yes
• Processor Series: HC08JB
• Core: HC08
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: USB
• Maximum Clock Frequency: 3 MHz
• Number Of Programmable I/os: 37
• Number Of Timers: 2
• Operating Supply Voltage: 4 V to 5.5 V
• Maximum Operating Temperature: + 70 C
• Mounting Style: Through Hole
• Development Tools By Supplier: FSICEBASE, DEMO908GZ60E, M68EML08GZE, KITUSBSPIDGLEVME, KITUSBSPIEVME, KIT33810EKEVME
• Minimum Operating Temperature: 0 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Details

11.5.4.2 Buffered PWM Signal Generation
MC68HC908JB8•MC68HC08JB8•MC68HC08JT8 — Rev. 2.3
Freescale Semiconductor
NOTE:
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.
Channels 0 and 1 can be linked to form a buffered PWM channel whose
output appears on the PTE1/TCH0 pin. The TIM channel registers of the
linked pair alternately control the pulse width of the output.
Setting the MS0B bit in TIM channel 0 status and control register (TSC0)
links channel 0 and channel 1. The TIM channel 0 registers initially
control the pulse width on the PTE1/TCH0 pin. Writing to the TIM
channel 1 registers enables the TIM channel 1 registers to
synchronously control the pulse width at the beginning of the next PWM
period. At each subsequent overflow, the TIM channel registers (0 or 1)
that control the pulse width are the ones written to last. TSC0 controls
and monitors the buffered PWM function, and TIM channel 1 status and
control register (TSC1) is unused. While the MS0B bit is set, the
channel 1 pin, PTE2/TCH1, is available as a general-purpose I/O pin.
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•
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)
Timer Interface Module (TIM)
Functional Description
Technical Data
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