usart.c

STM32的低功耗例程

/******************** (C) COPYRIGHT 2007 STMicroelectronics ********************
* File Name          : usart.c
* Author             : MCD Application Team
* Version            : V1.0
* Date               : 10/10/2007
* Description        : This file provides USART firmware functions
********************************************************************************
* THE PRESENT SOFTWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
* WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE TIME.
* AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY DIRECT,
* INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING FROM THE
* CONTENT OF SUCH SOFTWARE AND/OR THE USE MADE BY CUSTOMERS OF THE CODING
* INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
*******************************************************************************/

/* Includes ------------------------------------------------------------------*/
#include "stm32f10x_lib.h"
#include "usart.h"
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/  
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/ 

/*******************************************************************************
* Function Name  : GPIO_ConfigUSART
* Description    : Configures GPIO for USART1 using.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void GPIO_ConfigUSART(void)
{  
  GPIO_InitTypeDef GPIO_InitStructure;

  /* Configure USART1 Tx (PA.09) as alternate function push-pull */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_Init(GPIOA, &GPIO_InitStructure);
    
  /* Configure USART1 Rx (PA.10) as input floating */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
  GPIO_Init(GPIOA, &GPIO_InitStructure);
}

/*******************************************************************************
* Function Name  : USART_Configuration
* Description    : Configures the USART1.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void USART_Configuration(void)
{
 USART_InitTypeDef USART_InitStructure;
/* USART1 configuration ------------------------------------------------------*/
  /* USART1 configured as follow:
        - BaudRate = 115200 baud  
        - Word Length = 8 Bits
        - One Stop Bit
        - No parity
        - Hardware flow control disabled (RTS and CTS signals)
        - Receive and transmit enabled
        - USART Clock disabled
        - USART CPOL: Clock is active low
        - USART CPHA: Data is captured on the middle 
        - USART LastBit: The clock pulse of the last data bit is not output to 
                         the SCLK pin
  */
  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_Mode_Tx;
  USART_InitStructure.USART_Clock = USART_Clock_Disable;
  USART_InitStructure.USART_CPOL = USART_CPOL_Low;
  USART_InitStructure.USART_CPHA = USART_CPHA_2Edge;
  USART_InitStructure.USART_LastBit = USART_LastBit_Disable;

  USART_Init(USART1, &USART_InitStructure);
    
  /* Enable USART1 */
  USART_Cmd(USART1, ENABLE);
}



/*******************************************************************************
* Function Name  : fputc
* Description    : Retargets the C library printf function to the USART.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
int fputc(int ch, FILE *f)
{
  /* Place your implementation of fputc here */
  /* e.g. write a character to the USART */
  USART_SendData(USART1, (u8) ch);

  /* Loop until the end of transmission */
  while(USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET)
  {
  }

  return ch;
}

/*******************************************************************************
* Function Name  : USART_Scanf
* Description    : Gets numeric values from the hyperterminal.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
u8 USART_Scanf(u32 value)
{
  u32 index = 0;
  u32 tmp[2] = {0, 0};     
  
  while(index < 2)
  {
    /* Loop until RXNE = 1 */
    while(USART_GetFlagStatus(USART1, USART_FLAG_RXNE) == RESET)
    {
    }
    tmp[index++] = (USART_ReceiveData(USART1));
    if((tmp[index - 1] < 0x30) || (tmp[index - 1] > 0x39))
    {
      printf("\n\rPlease enter valid number between 0 and 9");
      index--;
    }
  }
  /* Calculate the Corresponding value */
  index = (tmp[1] - 0x30) + ((tmp[0] - 0x30) * 10); 
  /* Checks */
  if(index > value)
  {
    printf("\n\rPlease enter valid number between 0 and %d", value);
    return 0xFF;
  }
  return index;
}

/******************* (C) COPYRIGHT 2007 STMicroelectronics *****END OF FILE****/