DocID027369 Rev 1

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AN4646

Application example

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Application example

This application example demonstrate how to use the peripheral interconnect matrix on

STM32F401/411 lines and shows how to synchronize TIM peripherals in parallel mode.

This firmware is based on STM32F4xx HAL drivers which is part of STM32CubeF4.

3.1

Hardware description

Three timers are used in this example:

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TIM1 is configured as master timer:

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PWM mode is enabled

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TIM2 update event is used as trigger output.

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TIM2 and TIM3 are slaves for TIM1

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PWM mode is enabled

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ITR0(TIM1) is used as trigger input for both slave timers.

Figure 5. Application overview

1. The generator (TIM1) is shown in yellow, while the user blocks (TIM2 and TIM3) are highlighted in gray.

3.2

Software description

TIM1 counter clock is 84 MHz.

TIM1 master timer is running at TIM1 frequency:

•

TIM1 frequency = TIM1 counter clock/ (TIM1 period + 1) = 328.125 KHz

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The duty cycle is equal to TIM2_CCR1/ (TIM2_ARR + 1) = 25%.