Do I need to buy hardware for this tutorial?

No. Everything runs in the browser: Circuitly simulates the board, the components and the code. Real hardware is optional if you want to rebuild the circuit afterwards.

Which components are used?

Arduino UNO board. They are already available in the simulator library.

How long does it take?

About 15 minutes, advanced level, in 4 guided steps.

What should I know before starting?

The previous tutorial in the series, “Colour TFT screen over SPI”, is enough preparation. No software install is required.

Is the code provided and checked?

The simulator checks your wiring and your code automatically at every step, and shows the commented solution if you get stuck.

All tutorials

4 · Displays & buses

Scan the I²C bus

Advanced15 min

Goal

List the addresses of the devices present on the bus.

Why it matters

The first troubleshooting reflex: knowing who actually answers on the bus.

What you need

Arduino UNO board

Nothing to buy: every component below is simulated in the browser.

Steps

01Place several I²C components on the canvas.
02Sweep addresses 1 to 126 with a for loop.
03Test each address with beginTransmission()/endTransmission().
04Print those answering 0.

This tutorial runs inside the Circuitly simulator: your wiring and your code are checked automatically at every step.

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Frequently asked questions

Do I need to buy hardware for this tutorial?: No. Everything runs in the browser: Circuitly simulates the board, the components and the code. Real hardware is optional if you want to rebuild the circuit afterwards.
Which components are used?: Arduino UNO board. They are already available in the simulator library.
How long does it take?: About 15 minutes, advanced level, in 4 guided steps.
What should I know before starting?: The previous tutorial in the series, “Colour TFT screen over SPI”, is enough preparation. No software install is required.
Is the code provided and checked?: The simulator checks your wiring and your code automatically at every step, and shows the commented solution if you get stuck.

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