putchar.c

来自「8051试验程序 基础教材」· C语言 代码 · 共 30 行

/*              PUTCHAR.C

   The ANSI "putchar" function.

   The putchar function writes the character c to the
   output-stream pointed to by stream. 
   The function returns the character written. If an writing 
   error  occurs the putchar shall return EOF.

   $Name: V7_dot_30A $    

   Copyright 1986 - 1999 IAR Systems. All rights reserved.
*/

#include <io51.h>    

int putchar(int ch)
{
  if (ch == '\n')  {
    while (!SCON_bit.TI);
    SCON_bit.TI = 0;
    SBUF = 0x0d;
  }

while (!SCON_bit.TI);
  SCON_bit.TI = 0;
  return (SBUF = ch);
}