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usart2 problem

Question asked by hirsch.gilad on Feb 18, 2014
Latest reply on Feb 18, 2014 by sung.chen_chung
I'm working with the STM32F051 
I have this code which works for usart1 but not for usart2.
appreciate any help
-Gilad

#include "stm32f0xx.h"


#define UART2


#ifdef UART1
  #define USARTx USART1  
  #define DATA 0x31
#else
  #define USARTx USART2  
  #define DATA 0x32
#endif


void main(void)
{
  GPIO_InitTypeDef GPIO_InitStructure;
  USART_InitTypeDef USART_InitStructure;
 
  
  /* Enable GPIO A clock */
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
#ifdef  UART2 
  /* Enable USART2 clock */
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);
#else  
       /* Enable USART clock */
      RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);


      /* Configure the HSI as USART clock */
      RCC_USARTCLKConfig(RCC_USART1CLK_HSI);
#endif
  
  /* Configure USART Rx & Tx as alternate function */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_Level_3;//GPIO_Speed_40MHz;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
  GPIO_Init(GPIOA, &GPIO_InitStructure);
  
  /* Mux out USART2 Rx & Tx */
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_1/*GPIO_AF_USART2*/); // PA2 USART2_TX
  GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_1/*GPIO_AF_USART2*/); // PA3 USART2_RX
  
  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_Parity_None;
  USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
  USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
  
  /* USART configuration */
  USART_Init(USARTx, &USART_InitStructure);
  
  /* Enable USART */
  USART_Cmd(USARTx, ENABLE);
  
  while(1)
  {
    while(USART_GetFlagStatus(USARTx, USART_FLAG_TXE) == RESET); /* Waitwhile TX full */
    USART_SendData(USARTx, DATA);
  }
}

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