AN4013 datasheet(17/37 Pages) STMICROELECTRONICS

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AN4013

General-purpose timer modes

The following figure resumes the asymmetric behavior versus the center aligned PWM

mode

Figure 1. Asymmetric PWM mode versus center Aligned PWM mode

To configure the timer in this mode:

Configure the output pin:

Select the output mode by writing CCS bits in CCMRx register.

Select the polarity by writing the CCxP bit in CCER register.

Select the Asymmetric PWM mode (Asymmetric PWM1 or Asymmetric PWM2) by

writing OCxM bits in CCMRx register.

Program the period, the pulse length and the phase shift respectively in ARR, CCRx

and CCRy registers.

Select the counting mode: the Asymmetric PWM mode is working only with center

aligned mode: the counter mode must be center aligned counting mode (CMS bits

different from '00').

Enable the capture compare.

Enable the counter.

For more details on how to use the timer in this mode, refer to the examples provided in the

STM32F30x standard peripheral libraries, in the

/Project/STM32F30x_StdPeriph_Examples/ TIM/Asymmetric folders.

AN4013 데이터시트(PDF) 17 Page - STMicroelectronics