STM32F3xx microcontroller low-power application example

AN4538

18/25

DocID026505 Rev 1

2.2.2

Peripherals configuration

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Timer1

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TIM1_output: pin PA8.

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APB2 Prescaler = 1 (8 MHz)

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Period = 1/20 KHz

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Pulse = 50% of Period

–

OCref_clr is enabled to disable the PWM generation when high level is detected.

•

UART1

–

USART1_Tx (PA9), USART1_Rx (PA10)

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Baud Rate: 115200 bps

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Word length: 8 bits

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Stop bits: 1

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Hardware flow control and parity: none

–

UART wakeup from Stop mode: EXTI line 25

Note:

The virtual comport is connected to the USART2 in the NUCLEO-F302R8 board. Use

USART1 in the software to support the «USART wakeup from stop feature». USART2 pins

should be connected to USAR1 pins. The virtual comport software should be downloaded.

•

COMP2

–

COMP2 non inverting input (COMP2_INP): pin PA7

–

COMP2 inverting input (COMP2_INM): VREFINT or DAC1_OUT1

–

COMP outputs: TIM1_OCref_clr / COMP_OUT: pin PA12

–

COMP wakeup from Sleep mode: EXTI line 22

•

RTC

–

Clock source: LSE

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RTC_ASYNCH_PREDIV: 0x7F

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RTC_SYNCH_PREDIV: 0x00FF

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RTC_OUTPUT: disable

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Calendar: format12, hour, minute, second

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RTC wakeup: EXTI line 20 to wake up from standby.

•

DAC

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Channel: 1

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Data alignment: 12 bit data alignment.

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Data: 2500 (by default), it can be modified by the user.