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In this lesson we learn how to use MLX90614 touchless infrared temperature sensor with LCD1602 and Arduino.
/******
* Robojax Arduino Step By Step Course
* Part 4: Temperature Sensors
* Lesson 46, MLX90614 with LCD1602
This is a library example for the MLX90614 Temp Sensor
Original Library and code source: https://github.com/adafruit/Adafruit-MLX90614-Library
Please watch video instruction here https://youtu.be/IAj0gHTTWfw
This code is available at http://robojax.com/course1/?vid=lecture11
with over 100 lectures Free On YouTube Watch it here http://robojax.com/L/?id=338
Get the code for the course: http://robojax.com/L/?id=339
updated/written by Ahmad Shamshiri on Jun 28, 2020
or make donation using PayPal http://robojax.com/L/?id=64
* * This code is "AS IS" without warranty or liability. Free to be used as long as you keep this note intact.*
* This code has been download from Robojax.com
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
Origin
Written by Limor Fried/Ladyada for Adafruit Industries.
BSD license, all text above must be included in any redistribution
****************************************************/
#include <Wire.h>
#include <Adafruit_MLX90614.h>
char *typeName[]={"Object:","Ambient:"};
Adafruit_MLX90614 mlx = Adafruit_MLX90614();
#include <LiquidCrystal_I2C.h>
const uint8_t I2C_ADDRESS =0x3f;
const uint8_t LCD_CHAR= 16;
const uint8_t LCD_ROW= 2;
LiquidCrystal_I2C lcd(I2C_ADDRESS, LCD_CHAR,LCD_ROW);
void setup() {
//Robojax Step by Step Course http://robojax.com/L/?id=338
Serial.begin(9600);
Serial.println("Robojax MLX90614 test");
if (!mlx.begin()) //Begin returns 0 on a good init
{
lcd.print("MLX90614 Failed");
lcd.setCursor(0,1);
lcd.print("check wiring!");
while (1)
;
}
Wire.begin();
lcd.begin();
lcd.backlight();
lcd.print("Robojax MLX90614");
lcd.setCursor(0,1);
lcd.print("Infrared Temp.");
delay(2000);
clearCharacters(LCD_ROW-1,0, LCD_CHAR-1);
}//setup() end
void loop() {
//Robojax Example for MLX90614 with LCD
//Robojax Step by Step Course http://robojax.com/L/?id=338
printTemp('C');//object temperature in C
delay(2000);
printTemp('D');//ambient temperature in C
delay(2000);
//
// printTemp('F'); //object temperature in F
// delay(2000);
//
// printTemp('G'); //ambient temperature in F
// delay(2000);
// if( getTemp('C')>40)
// {
// //do something here
// }
//
// printTemp('K'); //object temperature in K
// delay(2000);
// printTemp('L');//ambient temperature in K
// delay(2000);
//Robojax Example for MLX90614
}
/*
* @brief returns temperature or relative humidity
* @param "type" is character
* C = Object Celsius
* D = Ambient Celsius
*
* K = Object Keliven
* L = Ambient in Keilven
*
* F = Object Fahrenheit
* G = Ambient in Fahrenheit
* @return returns one of the values above
* Usage: to get Fahrenheit type: getTemp('F')
* to print it on serial monitor Serial.println(getTemp('F'));
* Written by Ahmad Shamshiri on Mar 30, 2020.
* in Ajax, Ontario, Canada
* www.Robojax.com
*/
float getTemp(char type)
{
//Robojax Step by Step Course http://robojax.com/L/?id=338
// Robojax.com MLX90614 Code
float value;
float tempObjec = mlx.readObjectTempC();//in C object
float tempAmbient = mlx.readAmbientTempC();
if(type =='F')
{
value = mlx.readObjectTempF(); //Fah. Object
}else if(type =='G')
{
value = mlx.readAmbientTempF();//Fah Ambient
}else if(type =='K')
{
value = tempObjec + 273.15;// Object Kelvin
}else if(type =='L')
{
value = tempAmbient + 273.15;//Ambient Kelvin
}else if(type =='C')
{
value = tempObjec;
}else if(type =='D')
{
value = tempAmbient;
}
return value;
// Robojax.com MLX90614 Code
}//getTemp
/*
* @brief nothing
* @param "type" is character
* C = Object Celsius
* D = Ambient Celsius
*
* K = Object Keliven
* L = Ambient in Keilven
*
* F = Object Fahrenheit
* G = Ambient in Fahrenheit
* @return prints temperature value in serial monitor
* Usage: to get Fahrenheit type: getTemp('F')
* to print it on serial monitor Serial.println(getTemp('F'));
* Written by Ahmad Shamshiri on Mar 30, 2020 at 21:51
* in Ajax, Ontario, Canada
* www.Robojax.com
*/
void printTemp(char type)
{
clearCharacters(1,0, LCD_CHAR-1 );
// Robojax.com MLX90614 Code
float tmp =getTemp(type);
lcd.setCursor(0,1);
if(type =='C')
{
lcd.print(typeName[0]);
lcd.print(" ");
lcd.print(tmp);
lcd.print((char)223);//
lcd.print("C");
}else if(type =='D')
{
lcd.print(typeName[1]);
lcd.print(" ");
lcd.print(tmp);
lcd.print((char)223);//
lcd.print("C");
}else if(type =='F')
{
lcd.print(typeName[0]);
lcd.print(" ");
lcd.print(tmp);
lcd.print((char)223);//
lcd.print("F");
}else if(type =='G')
{
lcd.print(typeName[1]);
lcd.print(" ");
lcd.print(tmp);
lcd.print((char)223);//
lcd.print("F");
}
else if(type =='K')
{
lcd.print(typeName[0]);
lcd.print(" ");
lcd.print(tmp);
lcd.print((char)223);//
lcd.print("K");
}
else if(type =='L')
{
lcd.print(typeName[1]);
lcd.print(" ");
lcd.print(tmp);
lcd.print((char)223);//
lcd.print("K");
}
// Robojax.com MLX90614 Code
}//printTemp(char type)
/*
clearCharacters(uint8_t row,uint8_t start, uint8_t stop)
* @brief clears a line of display (erases all characters)
* @param none
* @return does not return anything
* Written by Ahmad Shamshiri
* www.Robojax.com code May 28, 2020 at 16:21 in Ajax, Ontario, Canada
*/
void clearCharacters(uint8_t row,uint8_t start, uint8_t stop )
{
for (int i=start; i<=stop; i++)
{
lcd.setCursor (i,row); //
lcd.write(254);
}
}//clearCharacters
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