wiringPi_Blueberry/examples/Gertboard/buttons.c
2023-08-11 15:53:17 +08:00

84 lines
2.1 KiB
C

/*
* buttons.c:
* Read the Gertboard buttons. Each one will act as an on/off
* tiggle switch for 3 different LEDs
*
* Copyright (c) 2012-2013 Gordon Henderson. <projects@drogon.net>
***********************************************************************
* This file is part of wiringPi:
* https://projects.drogon.net/raspberry-pi/wiringpi/
*
* wiringPi is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* wiringPi is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with wiringPi. If not, see <http://www.gnu.org/licenses/>.
***********************************************************************
*/
#include <stdio.h>
#include <wiringPi.h>
// Array to keep track of our LEDs
int leds [] = { 0, 0, 0 } ;
// scanButton:
// See if a button is pushed, if so, then flip that LED and
// wait for the button to be let-go
void scanButton (int button)
{
if (digitalRead (button) == HIGH) // Low is pushed
return ;
leds [button] ^= 1 ; // Invert state
digitalWrite (4 + button, leds [button]) ;
while (digitalRead (button) == LOW) // Wait for release
delay (10) ;
}
int main (void)
{
int i ;
printf ("Raspberry Pi Gertboard Button Test\n") ;
wiringPiSetup () ;
// Setup the outputs:
// Pins 3, 4, 5, 6 and 7 output:
// We're not using 3 or 4, but make sure they're off anyway
// (Using same hardware config as blink12.c)
for (i = 3 ; i < 8 ; ++i)
{
pinMode (i, OUTPUT) ;
digitalWrite (i, 0) ;
}
// Setup the inputs
for (i = 0 ; i < 3 ; ++i)
{
pinMode (i, INPUT) ;
pullUpDnControl (i, PUD_UP) ;
leds [i] = 0 ;
}
for (;;)
{
for (i = 0 ; i < 3 ; ++i)
scanButton (i) ;
delay (1) ;
}
}