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One pin of the GPIOA end of the stm32F103 core board is connected to an LED, and one pin of the GPIOB port is connected to a switch (replaced by DuPont line simulation). Interrupt mode programming is adopted. When the switch is connected to high level, the LED lights up; When connected to low level, the LED is off. And use the middle section to complete a USART serial communication program of STM32

catalogue

1. Middle section

1.1 meaning

1.2 intermediate process

  1.3 function

2. Use interrupt mode to light LED

2.1CubeMX generation project

2.2GPIO

  3. Burning procedure

  3.1 add code

  3.2 burning procedure

  3.3 effect display

4. Serial communication

4.1 establishment of the project

4.2 code

  V. summary

Vi. references

1. Middle section

1.1 meaning

The CPU temporarily stops the execution of the current program, turns to handle the temporary events, and returns to execute the original program after processing. Interrupt is a process that calls the corresponding handler (or service program) when an external event occurs. The interrupt service program and the program that the CPU is running at the time of interrupt are independent of each other and do not transfer data to each other.

1.2 intermediate process

  1.3 function

1. Preemptive priority

2. Responsive priority

  The characteristic of preemptive priority is that interrupts with high preemptive priority can be responded in the process of interrupt processing with low preemptive priority, that is, interrupt nesting.

2. Use interrupt mode to light LED

2.1CubeMX generation project

Create a new project
Select STM32F103C8 chip and click Start Project to enter the project
Configure the system debugging interface SYS and select Serial Wire
Configure the peripheral RCC and select HSE (external high-speed clock) as Crystal/Ceramic Resonator

2.2GPIO

Select LED pin PA5 and set pin to output mode GPIO_Output
Select pin PB1 as an external interrupt and set it to GPIO with the interrupt line_ Exti15 connection

GPIO_PA5 is named R

GPIO_PB1   It is named ZDUAN, and the trigger mode is selected as falling edge trigger  ， Select pull-up resistance

  Select NVIC

  Set interrupt priority

  set clock

  Finally, the keil5 project is generated

  3. Burning procedure

  3.1 add code

The code is as follows

/*
* @brief EXTI line detection callbacks. 
* @param GPIO_Pin: Specifies the pins connected EXTI line,
* @retval None 
*/ 
void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin) 
{ 
	if( GPIO_Pin == ZDUAN_Pin ) 
		{
			HAL_GPIO_TogglePin(R_GPIO_Port, R_Pin); 
		}
}

 

  3.2 burning procedure

  3.3 effect display

Note: since there is no switch, the middle section operation can only be carried out by wire grounding and non grounding instead of the switch

4. Serial communication

4.1 establishment of the project

Create a new project first, and the steps are the same as above

Setting RCC

Set SYS

  Select UASRT1, change the mode to asynchronous communication, and select NVIC Setting below

  Create project as above

4.2 code

First, define the length of an array to place the transmitted data

uint8_t OT_RxBuffer;		
uint8_t Uart1_RxBuff[1000];	
uint8_t Uart1_Rx_Cnt = 0;	

Write acceptance function

HAL_UART_Receive_IT(&huart1, (uint8_t *)&OT_RxBuffer, 1);

Enable function and send function

void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
  /* Prevent unused argument(s) compilation warning */
  UNUSED(huart);
  /* NOTE: This function Should not be modified, when the callback is needed,
           the HAL_UART_TxCpltCallback could be implemented in the user file
   */
		Uart1_RxBuff[Uart1_Rx_Cnt++] = OT_RxBuffer;   //??????
	
		if((Uart1_RxBuff[Uart1_Rx_Cnt-1] == 0x0A)&&(Uart1_RxBuff[Uart1_Rx_Cnt-2] == 0x0D)) 
		{
			HAL_UART_Transmit(&huart1, (uint8_t *)&Uart1_RxBuff, Uart1_Rx_Cnt,0xFFFF); 
			Uart1_Rx_Cnt = 0;
			//memset(Uart1_RxBuff,0x00,sizeof(Uart1_RxBuff)); 
		}
	
	HAL_UART_Receive_IT(&huart1, (uint8_t *)&OT_RxBuffer, 1);   
}

Compiler

  4.3 burning procedure

The final results are as follows

  V. summary

Through this experiment, I realized the light on and off with CUbeMX and the serial communication with the middle section, and learned some relevant knowledge of the middle section

Vi. references

Beginner STM32: Based on CubeMX, use interrupt to realize LED and serial communication_ LC Yusheng's blog - CSDN blog

HAL library STM32CubeMX realizes LED on and off - interrupt mode_ Blog of L-GRAZY - CSDN blog

stm32 novice must see a few simple steps to complete the external interrupt control light of the key with cubeMX (STM32F103RCT)_ Blog of zchh12 - CSDN blog_ stm32 external interrupt control led light on and off