优雅使用IAR9.3调用printf打印信息

/* Includes */

#include "stdio.h"





/*!

 * [url=home.php?mod=space&uid=247401]@brief[/url]       Redirect C Library function printf to serial port.

 *              After Redirection, you can use printf function.

 *

 * @param       ch:  The characters that need to be send.

 *

 * @param       *f:  pointer to a FILE that can recording all information

 *              needed to control a stream

 *

 * @retval      The characters that need to be send.

 */

int fputc(int ch, FILE *f)

{

    /** send a byte of data to the serial port */

    USART_TxData(DEBUG_USART,(uint8_t)ch);



    /** wait for the data to be send  */

    while (USART_ReadStatusFlag(DEBUG_USART, USART_FLAG_TXBE) == RESET);



    return (ch);

}

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

 *

 * Copyright 1998-2017 IAR Systems AB.

 *

 * This is a template implementation of the "__write" function used by

 * the standard library.  Replace it with a system-specific

 * implementation.

 *

 * The "__write" function should output "size" number of bytes from

 * "buffer" in some application-specific way.  It should return the

 * number of characters written, or _LLIO_ERROR on failure.

 *

 * If "buffer" is zero then __write should perform flushing of

 * internal buffers, if any.  In this case "handle" can be -1 to

 * indicate that all handles should be flushed.

 *

 * The template implementation below assumes that the application

 * provides the function "MyLowLevelPutchar".  It should return the

 * character written, or -1 on failure.

 *

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



#include <LowLevelIOInterface.h>

#include "Board.h"

#include "apm32f4xx.h"



#pragma module_name = "?__write"



uint8_t USART_Transmit(USART_T* usart, uint8_t *pdata, uint16_t Size);



/*

 * If the __write implementation uses internal buffering, uncomment

 * the following line to ensure that we are called with "buffer" as 0

 * (i.e. flush) when the application terminates.

 */



size_t __write(int handle, const unsigned char * buffer, size_t size)

{

  if (buffer == 0)

  {

    /*

     * This means that we should flush internal buffers.  Since we

     * don't we just return.  (Remember, "handle" == -1 means that all

     * handles should be flushed.)

     */

    return 0;

  }



  /* This template only writes to "standard out" and "standard err",

   * for all other file handles it returns failure. */

  if (handle != _LLIO_STDOUT && handle != _LLIO_STDERR)

  {

    return _LLIO_ERROR;

  }

  

  /* Sending in normal mode */

  if(USART_Transmit(USART1,(uint8_t *)buffer,size) == 1)

  {

    return size;

  }

  else

  {

    return _LLIO_ERROR;

  }

}



uint8_t USART_Transmit(USART_T* usart, uint8_t *pdata, uint16_t Size)

{

  uint8_t ch = 0;

  uint16_t i = 0;

  uint16_t timeout = 0x1000;

  

  for(i=0;i<Size;i++)

  {

    ch = pdata[i];

    

    /** send a byte of data to the serial port */

    USART_TxData(usart,(uint8_t)ch);



    /** wait for the data to be send  */

    while ((USART_ReadStatusFlag(usart, USART_FLAG_TXBE) == RESET) && (timeout -- ));

    

    if(timeout == 0)

    {

      return 0;

    }

    

    timeout = 0x1000;

    

  }

  

  return 1;

}