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usart communication : from usart3 to usart1

Question asked by louati.amir on Jan 14, 2014
Latest reply on Jan 14, 2014 by pablo
I wrote this code in order to test usart communication in fact When I press the user button an interruption in generated witch send data from usart3 to the usart1 when data is recived an interruption is generated witch togel the 4 leds in the board.

I connected the pin PB7 to the PB10 in the hardware. but it didn't work :/
I cheked by debugging the interruption is generated when i press the button so the problem look from the usart configuration.

#include "stm32f4xx.h"
#include "stm32f4xx_gpio.h"
#include "stm32f4xx_rcc.h"
#include "stm32f4xx_tim.h"
#include "stm32f4xx_usart.h"
#include "misc.h"
#include "stm32f4xx_exti.h"
#include "stm32f4xx_syscfg.h"
  
/*******************************************************************/
 
static void EXTILine0_Config(void)
{
  EXTI_InitTypeDef   EXTI_InitStructure;
  GPIO_InitTypeDef   GPIO_InitStructure;
  NVIC_InitTypeDef   NVIC_InitStructure;
   
  /* Enable GPIOA Clock */
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);
   
  /* Enable SYSCFG clock */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
   
  /* Configure PA0 pin as input floating */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
  GPIO_Init(GPIOA, &GPIO_InitStructure);
 
  /* Connect EXTI Line0 to PA0 pin */
  SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource0);
 
  /* Configure EXTI Line0 */
  EXTI_InitStructure.EXTI_Line = EXTI_Line0;
  EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
  EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising; 
  EXTI_InitStructure.EXTI_LineCmd = ENABLE;
  EXTI_Init(&EXTI_InitStructure);
 
  /* Enable and set EXTI Line0 Interrupt to the lowest priority */
  NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0F;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0F;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
}
 
/**************************************************************************************/
 
void LED_Configuration(void)
{
  /* GPIOD clock enable */
  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE);
   
  GPIO_InitTypeDef GPIO_InitStructure;
   
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12 | GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15;
  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_100MHz;
  GPIO_Init(GPIOD, &GPIO_InitStructure);
}
 
/**************************************************************************************/
 
void USART_configuration(void){
    // USART1 {RX : B7 ; TX : B6}
    // USART3 {RX : B11 ; TX : B10}
  /* USARTx configured as follow:
        - BaudRate = 9600 baud
        - Word Length = 8 Bits
        - Two Stop Bit
        - Odd parity
        - Hardware flow control disabled (RTS and CTS signals)
        - Receive and transmit enabled
  */
    /* GPIOB clock enable */
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);
    /* USART 1 & 3 clock enable */
    RCC_APB1PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE);
     
    GPIO_InitTypeDef GPIO_InitStructure;
  //config USART 1 & 3 config pin
      /*-------------------------- GPIO Configuration ----------------------------*/
      GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_11 |GPIO_Pin_6 | GPIO_Pin_7;
      GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
      GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
      GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
      GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
      GPIO_Init(GPIOB, &GPIO_InitStructure);
      
      /* Connect USART pins to AF */
      GPIO_PinAFConfig(GPIOB, GPIO_PinSource10, GPIO_AF_USART3);
      GPIO_PinAFConfig(GPIOB, GPIO_PinSource11, GPIO_AF_USART3);
      GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_USART1);
      GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_USART1);
 
  //config internal register for usar3 & usart1
      USART_InitTypeDef USART_InitStructure;
    
      USART_InitStructure.USART_BaudRate = 9600;
      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(USART1, &USART_InitStructure);
      USART_Cmd (USART1, ENABLE);
       
      USART_Init(USART3, &USART_InitStructure);
      USART_Cmd (USART3, ENABLE);
   
  //enable receive data interruption    
      USART_ITConfig(USART1,USART_IT_RXNE,ENABLE);
       
      NVIC_InitTypeDef   NVIC_InitStructure;
       
      NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
      NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0E;
      NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0F;
      NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
      NVIC_Init(&NVIC_InitStructure);
}
 
/***************************************************************************************/
 
void EXTI0_IRQHandler(void){
    EXTI_ClearITPendingBit(EXTI_Line0);
    USART_SendData(USART3,0X0F);  
    for(int i = 0; i<0XFFFFF; i++);
}
 
/**************************************************************************************/
  
void USART1_IRQHandler(void){
  uint16_t data = USART_ReceiveData(USART1);
  if (data == 0X0F){
    GPIO_ToggleBits(GPIOD, GPIO_Pin_12 | GPIO_Pin_13 | GPIO_Pin_14 | GPIO_Pin_15);
  }
}
 
/**************************************************************************************/
 
int main(void)
{  
   
  LED_Configuration();
   
  EXTILine0_Config();
   
  USART_configuration();
     
  while(1)
  {
  }
}
  
/**************************************************************************************/

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