K210 module-Serial communication (USART)

The tutorial controls the RGB light color of the K210 visual module through buttons.

The tutorial only introduces the standard library project code

Hardware connection

Since we have configured a special connection line, we only need to install it to the corresponding interface:

Control principle

• K210 visual module

The K210 visual module itself is a development board. For detailed use, please refer to the module supporting tutorial.

Download program

Connect the SD card of the K210 visual module to the computer through a card reader, rename the program file to main.py and copy it to the SD card, then reinstall the SD card into the SD card slot of the K210 visual module.

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The K210 visual module and development board case codes are in the same folder: the folder name will distinguish the development board to which the code belongs

Communication protocol

The development board program controls serial port 2 to send different data through the onboard KEY button;

The K210 visual module program will parse the data sent by the development board serial port 2 and control the color of the RGB light on the K210 visual module board according to the data.

Software configuration

Pin definition

Software code

Since the default pin function is the normal IO pin function, we need to use the default multiplexing function.

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Product supporting materials source code path: Attachment → Source code summary → 2.Extended_Course → 11.k210

Control function

The tutorial only briefly introduces the code, you can open the project source code to read it in detail.

USART2_init

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void USART2_init(u32 baudrate)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    USART_InitTypeDef USART_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure; 
    
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA , ENABLE);
    
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStructure);    

    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
    
    NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
      
    USART_InitStructure.USART_BaudRate = baudrate;
    USART_InitStructure.USART_WordLength = USART_WordLength_8b;
    USART_InitStructure.USART_StopBits = USART_StopBits_1;
    USART_InitStructure.USART_Parity = USART_Parity_No ;
    USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
    USART_Init(USART2, &USART_InitStructure); 
 
    USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);        
    //USART_ClearFlag(USART2,USART_FLAG_TC);
    USART_Cmd(USART2, ENABLE);
}

USART2_Send_U8

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void USART2_Send_U8(uint8_t ch)
{
    while (USART_GetFlagStatus(USART2, USART_FLAG_TXE) == RESET)
        ;
    USART_SendData(USART2, ch);
}

USART2_Send_ArrayU8

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void USART2_Send_ArrayU8(uint8_t *BufferPtr, uint16_t Length)
{
    while (Length--)
    {
        USART2_Send_U8(*BufferPtr);
        BufferPtr++;
    }
}

USART2_IRQHandler

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void USART2_IRQHandler(void)
{
    uint8_t Rx2_Temp;
    if (USART_GetITStatus(USART2, USART_IT_RXNE) != RESET)
    {
        USART_ClearITPendingBit(USART2, USART_IT_RXNE);
        Rx2_Temp = USART_ReceiveData(USART2);
        
        Deal_K210(Rx2_Temp);
    }
}

Experimental phenomenon

The K210.hex file generated by the project compilation is located in the OBJ folder of the K210 project. Find the K210.hex file corresponding to the project and use the FlyMcu software to download the program to the development board.

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The corresponding functions can only be realized when both the K210 visual module and the development board have downloaded the program

After the program is successfully downloaded: press the KEY button to switch the RGB light color of the K210 visual module.