I'm using keil and I was trying to send some data trough UART4 in STM32f407 board but when I use USART_SendData() function I couldn't get anything out of TX pin (PC10) (even a change on this pin) , here is my initialization :
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_UART4, ENABLE);
//UART4_TX PC.10
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_Init(GPIOC, &GPIO_InitStructure);
//USART3_RX PB.11
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_Init(GPIOC, &GPIO_InitStructure);
GPIO_PinAFConfig(GPIOC, GPIO_Pin_10, GPIO_AF_UART4);
GPIO_PinAFConfig(GPIOC, GPIO_Pin_11, GPIO_AF_UART4);
//Usart1 NVIC
NVIC_InitStructure.NVIC_IRQChannel = UART4_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3 ;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
USART_InitStructure.USART_BaudRate = Baud;
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_Mode_Tx;
USART_Init(UART4, &USART_InitStructure);
USART_ITConfig(UART4, USART_IT_RXNE, ENABLE);
USART_Cmd(UART4, ENABLE);
have I missed something in this code ? P.S : when I use Printf() function the program stuck in it .