FILE *stream via USART

[asttekin]

Hi,

I'am reading data through USART1 and USART2. I am sending the data over USART3 using printf. It works for a while but then stops.

Here is my code:

FILE *stream;
char *buf;
size_t len;
 
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
	if (huart->Instance == USART1)
	{
		uart_1_Ready	= SET;
		HAL_UART_Receive_IT (&huart1, UART_1_rxBuffer, UART_1_RX_BUFFER_SIZE);
 
		fprintf(stream, UART_1_rxBuffer);
	}
	else if (huart->Instance == USART2)
	{
		uart_2_Ready	= SET;
		HAL_UART_Receive_IT (&huart2, UART_2_rxBuffer, UART_2_RX_BUFFER_SIZE);
				
		fprintf(stream, UART_2_rxBuffer);
	}
}
void sendDataUsart3(void)
{
         if(len >= 600)
	{
		printf(buf);
		fclose(stream);
		free(buf);
		buf = (char *)realloc(buf, 600);
		stream = open_memstream(&buf, &len);
	}
}
int main(void)
{
    buf 		= (char *) malloc(600);
    stream	= open_memstream(&buf , &len);
....
}

[Bassett.David]

Hello asttekin,

Correct me if I'm wrong, but I don't think you should free(buf) before realloc(buff...). realloc is expecting a valid pointer to allocated memory(?)

Regards,

Dave

[Tesla DeLorean]

How do you ensure the buffers are properly NUL terminated?

Any code to recover the situation if the receiver overruns or gets some framing or parity error?

[asttekin]

Actually I don't know exactly how to do it.I am using FILE stream for the first time in a project.

I manually insert the NULL after each UART data read.The UART data receiving code is as follows.Same as USART2.

if (huart->Instance == USART1)
	{
		uart_1_Ready	= SET;
		uart_1_Timeout	= 0;
		HAL_UART_Receive_IT (&huart1, UART_1_rxBuffer, UART_1_RX_BUFFER_SIZE);
 
		tempUart_1_Val	= huart->Instance->DR;
 
		if (tempUart_1_Val == '$')
		{
			uart_1_record			= 1;
			nmea_1_InputBufferIndex	= 0;
			}
		if (uart_1_record)
		{
			nmea_1_InputBuffer[nmea_1_InputBufferIndex]	= tempUart_1_Val;
			nmea_1_InputBufferIndex++;
 
			if (tempUart_1_Val == 0x0A)
			{
				nmea_1_InputBuffer[nmea_1_InputBufferIndex]	= '\0';
				navDataInput_1_ChecksumHigh		= nmea_1_InputBuffer[nmea_1_InputBufferIndex - 4];
				navDataInput_1_ChecksumLow		= nmea_1_InputBuffer[nmea_1_InputBufferIndex - 3];
				uart_1_dataReceived				= 1;
				if(workingMode == MODE1)
				{
					nmea_1_InputBufferIndex			= 0;
				}
				if (workingMode == MODE2)
				{
					fprintf(stream, nmea_1_InputBuffer);
					memset(nmea_1_InputBuffer,'\0', NMEA_BUFFER_SIZE);
				}
				uart_1_record					= 0;
			}
		}
 
	}