setusart.c

51单片机的内存优化和中断的有用知识

	  
/*******************************************************************************
* Function Name  : USART_Configuration
* Description    : Configures the USART1.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/

#include <stm32f10x_lib.h>              /* STM32F10x Library Definitions      */
int GetKey (void) ;
int SendChar (int ch) ;

void SetupUSART (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);
}




/* Implementation of putchar (also used by printf function to output data)    */
int SendChar (int ch)  {                /* Write character to Serial Port     */

  USART_SendData(USART1, (unsigned char) ch);
  while (!(USART1->SR & USART_FLAG_TXE));
  return (ch);
}


int GetKey (void)  {                    /* Read character from Serial Port    */

  while (!(USART1->SR & USART_FLAG_RXNE));
  return (USART_ReceiveData(USART1));
}