This is a basic LCD voltmeter example
YOU SHOULD NOT MEASURE MORE THAN 5v or reverse the polarity, you risk causing permanent damage to your Arduino
I tested a 1.5v battery, the reading was 1.50v, using a multimeter I read 1.58v, so not too shabby a reading.
Code
#include #include int analogValue = 0; float voltage = 0; // Connections: Sainsmart LCD/Keypad shield LiquidCrystal lcd(8, 9, 4, 5, 6, 7); void setup() { //Serial.begin(9600); delay(1000); //setup the LCD lcd.begin(16, 2); // start the library lcd.setCursor(0,0); lcd.print(“Voltage”); //Serial.begin(9600); } void loop() { analogValue = analogRead(1); voltage = 0.0048*analogValue; lcd.setCursor(0,1); lcd.print(voltage); delay(1000); }