Posted on August 28, 2017 at 12:02 Hi,
I try to receive characters over USART1 using the StdPeriphLibrary (System Workbench STM32, MCU is SM32F103C8B), but after I get the data the program stuck (transmission works perfectly).
The ISR is:
void USART1_IRQHandler(void)
{
uint16_t rx;
if(USART_GetITStatus(USART1,USART_IT_RXNE)!=RESET) // check RX interrupt
{
rx = USART_ReceiveData(USART1);
led_toggle();
}
}
Whenever data arrives the LED should toggle, but nothing happens, just hangs the code.
USART settings:
void
USART1_Init(
void
)
{
/* USART configuration structure for USART1 */
USART_InitTypeDef usart1_init_struct;
/* Bit configuration structure for GPIOA PIN9 and PIN10 */
GPIO_InitTypeDef gpioa_init_struct;
/* Enalbe clock for USART1, AFIO and GPIOA */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1 | RCC_APB2Periph_AFIO |
RCC_APB2Periph_GPIOA, ENABLE);
/* GPIOA PIN9 alternative function Tx */
gpioa_init_struct.GPIO_Pin = GPIO_Pin_9;
gpioa_init_struct.GPIO_Speed = GPIO_Speed_50MHz;
gpioa_init_struct.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_Init(GPIOA, &gpioa_init_struct);
/* GPIOA PIN9 alternative function Rx */
gpioa_init_struct.GPIO_Pin = GPIO_Pin_10;
gpioa_init_struct.GPIO_Speed = GPIO_Speed_50MHz;
gpioa_init_struct.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &gpioa_init_struct);
/* Enable USART1 */
USART_Cmd(USART1, ENABLE);
/* Baud rate 9600, 8-bit data, One stop bit
* No parity, Do both Rx and Tx, No HW flow control
*/
usart1_init_struct.USART_BaudRate = 9600;
usart1_init_struct.USART_WordLength = USART_WordLength_8b;
usart1_init_struct.USART_StopBits = USART_StopBits_1;
usart1_init_struct.USART_Parity = USART_Parity_No ;
usart1_init_struct.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
usart1_init_struct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
/* Configure USART1 */
USART_Init(USART1, &usart1_init_struct);
/* Enable RXNE interrupt */
USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
/* Enable USART1 global interrupt */
NVIC_EnableIRQ(USART1_IRQn);
}
(the original code is from
http://pandafruits.com/stm32_primer/stm32_primer_uart.php
)
Polling the RX works well.
Is there any suggestions?
