shiftOut.c

/*
 * @file shiftOut.c
 *
 * @author Andy Lindsay
 *
 * @version 0.85
 *
 * @copyright Copyright (C) Parallax, Inc. 2012.  See end of file for
 * terms of use (MIT License).
 *
 * @brief shiftOut function source, see simpletools.h for documentation.
 *
 * @detail Please submit bug reports, suggestions, and improvements to
 * this code to editor@parallax.com.
 */
 
#include "simpletools.h"                         // simpletools function prototypes
 
void shift_out(int pinDat, int pinClk, int mode, int bits, int value)
{
  int vi, vf, inc;
  set_direction(pinDat, 1);
  if(mode == LSBFIRST)
  {
    vi = 0;
    vf = bits;
    inc = 1;
  }
  else
  {
    vi = bits - 1;
    vf = -1;
    inc = -1;
  }
  low(pinClk);
  int i;
  for(i = vi; i != vf; i += inc)
  {
    set_output(pinDat, (value >> i) & 1);
    toggle(pinClk);
    toggle(pinClk);
  }
}