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ddr4s / fw / wiringPi / examples / okLed.c @ 32:cadb9025f1e0

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/*
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 * okLed.c:
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 *      Make the OK LED on the Pi Pulsate...
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 *
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 * Originally posted to the Raspberry Pi forums:
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 *  http://www.raspberrypi.org/phpBB3/viewtopic.php?p=162581#p162581
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 *
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 * Compile this and store it somewhere, then kick it off at boot time
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 *    e.g. by putting it in /etc/rc.local and running it in the
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 *    background &
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 *
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 * Copyright (c) 2012-2013 Gordon Henderson. <projects@drogon.net>
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 ***********************************************************************
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 * This file is part of wiringPi:
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 *        https://projects.drogon.net/raspberry-pi/wiringpi/
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 *
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 *    wiringPi is free software: you can redistribute it and/or modify
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 *    it under the terms of the GNU Lesser General Public License as published by
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 *    the Free Software Foundation, either version 3 of the License, or
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 *    (at your option) any later version.
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 *
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 *    wiringPi is distributed in the hope that it will be useful,
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 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
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 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 *    GNU Lesser General Public License for more details.
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 *
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 *    You should have received a copy of the GNU Lesser General Public License
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 *    along with wiringPi.  If not, see <http://www.gnu.org/licenses/>.
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 ***********************************************************************
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 */
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#include <stdio.h>
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#include <errno.h>
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#include <string.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <math.h>
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#include <wiringPi.h>
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#include <softPwm.h>
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// The OK/Act LED is connected to BCM_GPIO pin 16
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#define OK_LED  16
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int main ()
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{
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  int fd, i ;
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  wiringPiSetupGpio () ;
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// Change the trigger on the OK/Act LED to "none"
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  if ((fd = open ("/sys/class/leds/led0/trigger", O_RDWR)) < 0)
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  {
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    fprintf (stderr, "Unable to change LED trigger: %s\n", strerror (errno)) ;
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    return 1 ;
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  }
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  write (fd, "none\n", 5) ;
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  close (fd) ;
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  softPwmCreate (OK_LED, 0, 100) ;
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  for (;;)
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  {
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    for (i = 0 ; i <= 100 ; ++i)
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    {
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      softPwmWrite (OK_LED, i) ;
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      delay (10) ;
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    }
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    delay (50) ;
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    for (i = 100 ; i >= 0 ; --i)
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    {
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      softPwmWrite (OK_LED, i) ;
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      delay (10) ;
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    }
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    delay (10) ;
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  }
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  return 0 ;
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}