[ARM] STM32-UART-single-wire-half-duplex-communication

[surendran_raj]

I tried to make Single-wire half-duplex communication in UART using the STM32F103C8 controller. in single-wire half-duplex communication, a TX pin is used for transmitting and receiving the data. I had configured the pins and register with the help of a datasheet(reference manual for STM32F103C8). so I tried to transmit the data from one bluepill board(STM32F103C8) and to receive the data in another bluepill board(STM32F103C8). But I can't able to transmit and receive data. I have enclosed my code. Can anyone help me to solve it? I have used the register for the code.

Communication: USART3

Pins: PB10-TX, PB11-RX

STM32 reference manual

here is my code

#include<stm32f10x.h>

char receive;
void USART3_init(void)
{
    RCC->APB1ENR |= RCC_APB1ENR_USART3EN ;
    USART3->BRR = 0x0EA6;  //0x1D4C //0x0EA6
    USART3->CR3 |= USART_CR3_HDSEL;
    USART3->CR1 |= USART_CR1_RE | USART_CR1_RXNEIE;
    USART3->CR1 |= USART_CR1_TE | USART_CR1_TXEIE;
    USART3->CR1 |= USART_CR1_TCIE;
    
    USART3->CR1 |= USART_CR1_UE;
    NVIC_EnableIRQ(USART3_IRQn);
}
int main()
{
    RCC->APB2ENR |= RCC_APB2ENR_IOPBEN | RCC_APB2ENR_AFIOEN;
    GPIOB->CRH = 0x00000F00;
    
    USART3_init();
    
    while(1)
    {
        
    }
}

void USART3_IRQHandler(void)
{   
    USART3->DR = data;
    while((USART3->SR & USART_SR_TC) !=USART_SR_TC);
    USART3->SR &= ~USART_SR_TC;

}

 

[KlausST]

Hi,

Variable "receive" is never used.

I don't dive deeply into uncommented code.

Klaus

 

[surendran_raj]

Hi,

Variable "receive" is never used.

I don't dive deeply into uncommented code.

Klaus

thanks for your response first need to transmit the data in that condition data is not transmitted yet.

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