Figure 119. Center-Aligned Pwm Waveforms (Arr=8) - STMicroelectronics STM32F405 Reference Manual

Advanced-control timers (TIM1&TIM8)
PWM center-aligned mode
Center-aligned mode is active when the CMS bits in TIMx_CR1 register are different from
'00' (all the remaining configurations having the same effect on the OCxRef/OCx signals).
The compare flag is set when the counter counts up, when it counts down or both when it
counts up and down depending on the CMS bits configuration. The direction bit (DIR) in the
TIMx_CR1 register is updated by hardware and must not be changed by software. Refer to
Section : Center-aligned mode (up/down counting) on page
Figure 119
•
TIMx_ARR=8,
•
PWM mode is the PWM mode 1,
•
The flag is set when the counter counts down corresponding to the center-aligned
mode 1 selected for CMS=01 in TIMx_CR1 register.
536/1731
shows some center-aligned PWM waveforms in an example where:

Figure 119. Center-aligned PWM waveforms (ARR=8)

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