在MDK使用printf&scanf

在project的option for...分頁Target在Code Generation勾選Use MicroLIB.

在C Code加入程式碼，將printf、scanf底層函式fputc、fgetc導向USART

/* Includes ------------------------------------------------------------------*/

#include "stdio.h"

/* Private function prototypes -----------------------------------------------*/

#ifdef __GNUC__

  /* With GCC/RAISONANCE, small printf (option LD Linker->Libraries->Small printf

     set to 'Yes') calls __io_putchar() */

  #define PUTCHAR_PROTOTYPE int __io_putchar(int ch)

  #define GETCHAR_PROTOTYPE int __io_getchar(void)

#else

  #define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)

  #define GETCHAR_PROTOTYPE int fgetc(FILE *f)

#endif /* __GNUC__ */

/*******************************************************************************

* Function Name  : PUTCHAR_PROTOTYPE

* Description    : Retargets the C library printf function to the USART.

* Input          : None

* Output         : None

* Return         : None

*******************************************************************************/

PUTCHAR_PROTOTYPE

{

  /* Write a character to the USART */

  USART_SendData(USARTx, (u8) ch);

  /* Loop until the end of transmission */

  while(USART_GetFlagStatus(USARTx, USART_FLAG_TXE) == RESET)

  {

  }

  return ch;

}

/*******************************************************************************

* Function Name  : GETCHAR_PROTOTYPE

* Description    : Retargets the C library scanf function from the USART.

* Input          : None

* Output         : None

* Return         : None

*******************************************************************************/

GETCHAR_PROTOTYPE

{

   /* Loop until the end of receive */

   while(!(USART_GetFlagStatus(USART1, USART_FLAG_RXNE) == SET))

   {

   }

  

   /* Read a character to the USART */

   return (USART_ReceiveData(USART1));

}