Posted on September 20, 2014 at 11:50With my STM32F4 discovery board I cannot get the UART4_IRQHandler to be triggered on incoming serial data. However the USART2_IRQHandler functions as expected and when the data is ready from the UART4 RX data registered and transmitted out it works without a problem, only the interrupt will not work.
Initialisation
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void uartLink_init(void){
USART_InitTypeDef USART_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_UART4, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART6, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_Init(GPIOC, &GPIO_InitStructure);
GPIO_SetBits(GPIOC, GPIO_Pin_9);
GPIO_PinAFConfig(GPIOC, GPIO_PinSource6, GPIO_AF_USART6);
GPIO_PinAFConfig(GPIOC, GPIO_PinSource11, GPIO_AF_UART4);
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_11;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOC, &GPIO_InitStructure);
USART_InitStructure.USART_BaudRate = 115200;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;
USART_InitStructure.USART_StopBits = USART_StopBits_1;
USART_InitStructure.USART_Parity = USART_Parity_No;
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_InitStructure.USART_Mode = USART_Mode_Rx;
/* USART Rx configuration */
USART_Init(UART4, &USART_InitStructure);
/* USART Tx configuration */
USART_InitStructure.USART_Mode = USART_Mode_Tx;
USART_Init(USART6, &USART_InitStructure);
NVIC_InitStructure.NVIC_IRQChannel = UART4_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
/* Enable USART */
USART_Cmd(UART4, ENABLE);
USART_Cmd(USART6, ENABLE);
messageStatus = fingerDataWait;
}
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Interrupt
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void UART4_IRQHandler(void){
uint8_t data = USART_ReceiveData(UART4);
USART_SendData(USART6, data);
}
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Main loop
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int main(void)
{
prvSetupHardware();
uartLink_init();
power_GPS(POWER_ON);
gps_init();
while(1)
{
if (USART_GetFlagStatus(UART4, USART_FLAG_RXNE) != RESET)
{
uint16_t x = USART_ReceiveData(UART4);
while(USART_GetFlagStatus(USART6, USART_FLAG_TXE) == RESET);
USART_SendData(USART6, x);
}
}
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Interestingly with the GPS unit powered and configured as a serial with an interrupt it does not retrun to the main loop when in the debug state. However On the main application which has a freeRTOS implementation it works without problem. This information is possible inconsiquential to the uart4 fault i am having
#irq #stm32f429discovery #uart4
