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, 5 mm LED, 220 Ω resistor, Clavier 4x4. They are already available in the simulator library.

How long does it take?

About 18 minutes, intermediate level, in 4 guided steps.

What should I know before starting?

The previous tutorial in the series, “Understanding the SPI bus”, 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

5 · Communication & data

Control the board from the keyboard

Intermediate18 min

Goal

Switch the LED on/off with the “on” and “off” commands.

Why it matters

Parsing a text command is already writing a protocol.

What you need

Arduino UNO board
5 mm LED
220 Ω resistor
Clavier 4x4

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

Steps

01Serial.begin(9600).
02Test Serial.available(), then read the line.
03Compare the received command and act on it.
04Send back an acknowledgement.

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, 5 mm LED, 220 Ω resistor, Clavier 4x4. They are already available in the simulator library.
How long does it take?: About 18 minutes, intermediate level, in 4 guided steps.
What should I know before starting?: The previous tutorial in the series, “Understanding the SPI bus”, 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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