Introduction: Creating an Ohmmeter With Arduno

Greetings staff!

I'm Gabriel and I work on the Short Circuit. We are starting a project to disseminate knowledge in Arduino, ESP, RF Lora and many other things. As an initial test of our way of working, we will be posting an extremely basic tutorial on how to do an Ohmmeter with an Arduino.


To create a resistance measurement tool (Ohmmeter), which will be used to demonstrate the value of two resistors individually through the serial monitor of the Arduino programming software.

Use the following components:

Arduino Uno
Protoboard 400
Resistor 330R

Follow these steps:

- Fit two jumpers, one between the GND and the negative row, and another between the 5 V and the positive row. Then interconnect the power and GND rows.

- Connect two 330 Ω resistors by attaching one terminal 5-9 and the second one in the bottom row at position 9-13 ..

- Connect a black jumper between the negative of the Protoboard and one of the insulated terminals of the resistors, repeat the same to the other resistor by fitting the jumper in the positive row.

- Attach a jumper between an Arduino analog port (A0) in row 9, where the two resistors are connected;

- Open the programming software, and write:

// Projeto Curto Circuito – Ohmímetro

int R= 1000; // Resistor base (valor conhecido)
float t=0;
float V=0; // Tensão de saída
int x; // Leitor analógicoint
resultado=0; // Valor do resistor desconhecido

void setup()

pinMode(A0, INPUT); // Porta analógica
Serial.begin(9600); // Leitor Serial

void loop()

x = analogRead(A0);
t = x*5;
V= (t)/1024;
resultado= t*R;
Serial.println("Valor do Resistor:"); // Show message
Serial.println(resultado); // Shows the value of the variable

- Transfer the programming to the Arduino and click on the magnifying glass to visualize the circuit reading;

Okay, an ohmmeter made easy and fast.

This and many other projects you will find at: