USART Not Receiving Data (Polling)

Posted on May 31, 2017 at 17:06

Hi guys,

So I'm using an STM32F1 and am trying to send data from a serial terminal (RealTerm) to USART3 via a FTDI USB-UART converter cable. I have written code to poll for data on the RX line but for some reason my USART_FLAG_RXNE is not being set when I send data from the terminal. Here is my code (no errors):

void USART3_Config(void)

{

GPIO_InitTypeDef GPIO_InitStruct;

USART_InitTypeDef USART_InitStruct;

// Clock Config

RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3,ENABLE);

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);

RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);

// GPIO Config

GPIO_InitStruct.GPIO_Pin = GPIO_Pin_10; // USART3 TX

GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_PP;

GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_Init(GPIOB, &GPIO_InitStruct);

GPIO_InitStruct.GPIO_Pin = GPIO_Pin_11; // USART3 RX

GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IN_FLOATING;

GPIO_Init(GPIOB, &GPIO_InitStruct);

// USART Struct Config

USART_InitStruct.USART_BaudRate = 9600;

USART_InitStruct.USART_StopBits = USART_StopBits_1;

USART_InitStruct.USART_WordLength = USART_WordLength_8b;

USART_InitStruct.USART_Parity = USART_Parity_No;

USART_InitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;

USART_InitStruct.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;

USART_Init(USART3, &USART_InitStruct);

USART_Cmd(USART3, ENABLE);

}

int main(void)

{

RCC_Configuration();

...

USART3_Config();

...

while(1)

{

...

State = POLLING_TEST;

switch (State)

{

...

case POLLING_TEST:

while(USART_GetFlagStatus(USART3, USART_FLAG_RXNE) == RESET);

sprintf(data, 'dummy'); // breakpoint here

break;

Can anyone help me with this? Have I done something wrong?

Cheers,

Tony

#stm32f1 #usart #rx #polling