robolcd.ino

#include <Wire.h>
#include <LCD.h>
#include <LiquidCrystal_I2C.h>
#include <stdio.h>
#include <stdlib.h>

#define I2C_ADDR 0x3F
#define BACKLIGHT_PIN 3
#define En_pin 2
#define Rw_pin 1
#define Rs_pin 0
#define D4_pin 4
#define D5_pin 5
#define D6_pin 6
#define D7_pin 7

#define ESTOP_PIN 2
#define TEMP_PIN 0
LiquidCrystal_I2C lcd(I2C_ADDR, En_pin, Rw_pin, Rs_pin, D4_pin, D5_pin, D6_pin, D7_pin);

float LM35_temp()
{
    return 110 * (float) analogRead(TEMP_PIN) / 1024;
}

char stemp[10];

void setup()
{
    estop = false;
    pinMode(ESTOP_PIN, INPUT_PULLUP);
    analogReference(INTERNAL);
    Serial.begin(9600);
    lcd.begin(20, 4);
    lcd.setBacklightPin(BACKLIGHT_PIN, POSITIVE);
    lcd.setBacklight(HIGH);

    lcd.home();
    lcd.print("InMotion Robot v4");
    lcd.setCursor(0, 1);
    lcd.print("System Operational");
    lcd.setCursor(0, 3);
    lcd.print("Temperature: ");
}

unsigned long i = 0;
unsigned long starttime = 0;
void loop()
{
    i++;
    if (millis() % 500 == 0) {                   // silly to update more than 2Hz
        dtostrf(LM35_temp(), 6, 1, stemp);
        Serial.println(stemp);
        Serial.println(i);
        lcd.setCursor(13, 3);
        lcd.print(stemp);
        lcd.setCursor(9, 2);
        lcd.print((millis() - starttime) / 1000);
    }
    if (estop && digitalRead(ESTOP_PIN) == LOW) {
        estop = !estop;
        lcd.setCursor(0, 2);
        lcd.print("STOPPED:      ");
        starttime = millis();
    } else if (!estop && digitalRead(ESTOP_PIN) == HIGH) {
        estop = !estop;
        lcd.setCursor(0, 2);
        lcd.print("RUNNING:      ");
        starttime = millis();
    }
}