/*
* temperature.c:
* Demonstrate use of the Gertboard A to D converter to make
* a simple thermometer using the LM35.
*
* Copyright (c) 2012-2013 Gordon Henderson.
***********************************************************************
* This file is part of wiringPi:
* https://github.com/WiringPi/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 .
***********************************************************************
*/
#include
#include
#include
int main ()
{
int x1, x2 ;
double v1, v2 ;
printf ("\n") ;
printf ("Gertboard demo: Simple Thermemeter\n") ;
printf ("==================================\n") ;
// Always initialise wiringPi. Use wiringPiSys() if you don't need
// (or want) to run as root
wiringPiSetupSys () ;
// Initialise the Gertboard analog hardware at pin 100
gertboardAnalogSetup (100) ;
printf ("\n") ;
printf ("| Channel 0 | Channel 1 | Temperature 1 | Temperature 2 |\n") ;
for (;;)
{
// Read the 2 channels:
x1 = analogRead (100) ;
x2 = analogRead (101) ;
// Convert to a voltage:
v1 = (double)x1 / 1023.0 * 3.3 ;
v2 = (double)x2 / 1023.0 * 3.3 ;
// Print
printf ("| %6.3f | %6.3f |", v1, v2) ;
// Print Temperature of both channels by converting the LM35 reading
// to a temperature. Fortunately these are easy: 0.01 volts per C.
printf (" %4.1f | %4.1f |\r", v1 * 100.0, v2 * 100.0) ;
fflush (stdout) ;
}
return 0 ;
}