Convert to volts (map & float)

Goal

Turn the ADC's 0–1023 into a 0.00–5.00 V reading.

Why it matters

A raw reading means nothing: scaling is the heart of instrumentation.

Steps

1. 01Read A0.
2. 02Compute volts = value * 5.0 / 1023.0 (watch out for floats).
3. 03Print with 2 decimals: Serial.println(volts, 2).

Next tutorials

• Read a push button

  Light the LED only while the button is pressed.

• Toggle button (debounced)

  One press turns on, the next turns off — with no contact bounce.

• Read a potentiometer

  Print the analog value of A0 on the serial monitor.

• Light sensor (LDR)

  Turn the LED on automatically when the room gets dark.