USART_WakeUpFromStop_Init Example Description

Configuration of GPIO and USART1 peripherals to allow the characters received on USART_RX pin to wake up the MCU from low-power mode. This example is based on the STM32C0xx USART1 LL API. The peripheral initialization uses LL unitary service functions for optimization purposes (performance and size).

USART1 Peripheral is configured in asynchronous mode (9600 bauds, 8 data bit, 1 start bit, 1 stop bit, no parity). No HW flow control is used. USART1 Clock is based on HSI.

Example execution:

After startup from reset and system configuration, LED4 is blinking quickly during 3 sec, then MCU enters “Stop 0” mode (LED4 off). On first character reception by the USART1 from PC Com port (ex: using HyperTerminal) after “Stop 0” Mode period, MCU wakes up from “Stop 0” Mode. Received character value is checked :

In case of errors, LED4 is slowly blinking (1 sec period).

Keywords

Connectivity, UART/USART, Asynchronous, RS-232, baud rate, Interrupt, HyperTerminal, Receiver, Asynchronous, Low Power, Wake Up

Directory contents

Hardware and Software environment

How to use it ?

In order to make the program work, you must do the following :