temperature indicator.ino

//www.edisonsciencecorner.blogspot.com
//www.edisonsciencecorner.blogspot.com
//www.edisonsciencecorner.blogspot.com
//www.edisonsciencecorner.blogspot.com

#include <LedControl.h>
int lm35_pin = A0;
int DIN = 8;
int CS  = 9;
int CLK = 10;
 
LedControl lc = LedControl(DIN, CLK, CS, 0);
 
byte smile[8]  = {0x3C,0x42,0xA5,0x81,0xA5,0x99,0x42,0x3C};
byte sad[8]    = {0x3C,0x42,0xA5,0x81,0x99,0xA5,0x42,0x3C}; 
byte nuetral[8]= {0x3C,0x42,0xA5,0x81,0xBD,0x81,0x42,0x3C};
void setup() {
    lc.shutdown(0, false);    //The MAX72XX is in power-saving mode on startup
    lc.setIntensity(0, 15);   // Set the brightness to maximum value
    lc.clearDisplay(0);       // and clear the display
    Serial.begin(9600);
}
 
void loop() {
  int temp_adc_val;
  float temp_val;
  temp_adc_val = analogRead(lm35_pin);  /* Read Temperature */
  temp_val = (temp_adc_val * 4.88);      /* Convert adc value to equivalent voltage */
  temp_val = (temp_val/10);             /* LM35 gives output of 10mv/°C */
  Serial.print("Temperature = ");
  Serial.print(temp_val);
  Serial.print(" Degree Celsius\n");
  delay(1000);
    if (temp_val<35) {
        printByte(smile);
    } 
     if (temp_val>35 && temp_val<40) {
        printByte(nuetral);
    }
      if (temp_val>40) {
        printByte(sad);
    }
 
    delay(1000);
}
 
void printByte(byte character []) {
    int i = 0;
    for(i = 0; i < 8; i++) {
        lc.setRow(0, i, character[i]);
    }
}