Posted on April 19, 2014 at 17:21
Hello Yora,
It's nearly impossible to help you without seeing your code, specifically the initialization of the vector table and your usart init code. The best thing we can do is point you to example code which are already available on the internet.
But just guessing did you actually enable the interrupt you want to int on USART_ITConfig()? Did you follow all of the instructions at the top of
stm32f4xx_usart.c
[..]
(#) Enable peripheral clock using the following functions
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USARTx, ENABLE) for USART1 and USART6
RCC_APB1PeriphClockCmd(RCC_APB1Periph_USARTx, ENABLE) for USART2, USART3,
UART4 or UART5.
(#) According to the USART mode, enable the GPIO clocks using
RCC_AHB1PeriphClockCmd() function. (The I/O can be TX, RX, CTS,
or/and SCLK).
(#) Peripheral's alternate function:
(++) Connect the pin to the desired peripherals' Alternate
Function (AF) using GPIO_PinAFConfig() function
(++) Configure the desired pin in alternate function by:
GPIO_InitStruct->GPIO_Mode = GPIO_Mode_AF
(++) Select the type, pull-up/pull-down and output speed via
GPIO_PuPd, GPIO_OType and GPIO_Speed members
(++) Call GPIO_Init() function
(#) Program the Baud Rate, Word Length , Stop Bit, Parity, Hardware
flow control and Mode(Receiver/Transmitter) using the USART_Init()
function.
(#) For synchronous mode, enable the clock and program the polarity,
phase and last bit using the USART_ClockInit() function.
(#) Enable the NVIC and the corresponding interrupt using the function
USART_ITConfig() if you need to use interrupt mode.
(#) When using the DMA mode
(++) Configure the DMA using DMA_Init() function
(++) Active the needed channel Request using USART_DMACmd() function
(#) Enable the USART using the USART_Cmd() function.
(#) Enable the DMA using the DMA_Cmd() function, when using DMA mode.
