Posted on December 17, 2015 at 09:23Hi,
I'm using uVision5 on windows7 to build and flash download but doing the experiment on Linux machine.(because UART COM port doesn't work on my win7 PC. I think this is a driver problem.). I've slightly modified the Uart_printf project so that the program prints something and receives commands from the console and prints it back. Below is the main() program.
============ in main.c ===============
char Rx_indx, Rx_data[2], Rx_Buffer[100], Transfer_cplt;
UART_HandleTypeDef UartHandle;
char buffer[100];
int len;
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
uint8_t i;
if (huart->Instance == USART2) // current UART
{
if (Rx_indx==0) {for (i=0;i<100;i++) Rx_Buffer[i] = 0; }
if (Rx_data[0] != 13) // if not enter
{
Rx_Buffer[Rx_indx++] = Rx_data[0]; // add data to Rx_Buffer
}
else {
Rx_indx = 0;
Transfer_cplt=1; // transfer complete, data is ready to be read
}
HAL_UART_Receive_IT(&UartHandle, (uint8_t *)Rx_data, 1); // reactivate
}
}
int main(void)
{
HAL_Init();
SystemClock_Config();
-- set USART2
...
HAL_UART_Receive_IT(&UartHandle, (uint8_t *)Rx_data, 1);
printf(''hello, World!\r\n'');
while (1) {
if (Transfer_cplt)
{
sprintf(buffer, ''%s\r\n'', Rx_Buffer);
len = strlen(buffer);
HAL_UART_Transmit(&UartHandle, (uint8_t *)buffer, len, 1000);
Transfer_cplt = 0;
}
}
while (1)
{
}
}
======= in stm32f4xx_it.c ================
void SysTick_Handler(void)
{
HAL_IncTick();
HAL_SYSTICK_IRQHandler();
}
void USART2_IRQHandler(void)
{
printf(''USART2_IRQHandler called\n\r''); <==== !!! not work without this line.
HAL_UART_IRQHandler(&UartHandle);
}
========== end of code =========
Below is the execution result when I have the ''USART2_IRQHandler called'' print in the USART2_IRQHandler(void) function.
hello, World!
USART2_IRQHandler called
USART2_IRQHandler called
USART2_IRQHandler called
USART2_IRQHandler called
USART2_IRQHandler called
abcd
USART2_IRQHandler called
USART2_IRQHandler called
USART2_IRQHandler called
USART2_IRQHandler called
USART2_IRQHandler called
efgh
USART2_IRQHandler called
USART2_IRQHandler called
USART2_IRQHandler called
USART2_IRQHandler called
USART2_IRQHandler called
xyzg
hello, World!
USART2_IRQHandler called
USART2_IRQHandler called
USART2_IRQHandler called
USART2_IRQHandler called
USART2_IRQHandler called
abcd
But if I remove the print (''USART2_IRQHandler called'') the print-back is not shown. What is wrong with the code?
