LEDs, buttons and buzzer
Digital outputs and inputs: the first circuit of every project.
Virtual laboratory · beta
Impeca Lab: write Arduino code and watch the circuit work in your browser
Pick an example, change the code and press Run. Nothing to install and no components to buy.
The test bench
Pick an example, change the code and press Run. Press the circuit’s button or move the sliders to test the inputs.
This first version runs your Arduino code with our own interpreter, in your browser. It understands variables, loops, functions, Serial, Servo and LiquidCrystal. It does not emulate the microcontroller or the other libraries yet: they come in later phases.
Arduino is a trademark of its owners. Impeca Lab is an independent project: it is not affiliated with or endorsed by Arduino. “Arduino-compatible” describes the language and the UNO board we use.
What works today and what is next
We would rather tell you clearly what you can use now and what we are preparing, with no made-up dates.
Available today
- Arduino UNO board with pins D2–D13 and A0–A5, the built-in “L” LED and the transmit LED.
- Five-colour LEDs, RGB LED, button, buzzer with sound, servo, potentiometer, photoresistor, temperature sensor and 16×2 LCD.
- 3D view of the bench: board, breadboard, resistors and jumper wires. The LED glows, the servo turns, and you can press the button or turn the knob right on the part. The 2D view is still available.
- Editor with colours, line numbers and error messages in your language.
- Serial console with input, and adjustable simulation speed.
- Ready-made examples, from the blinking LED to a voltmeter with a screen.
- Your work is saved in this browser and you can download the code as an .ino file.
In preparation
- Build the circuit yourself: drag components and draw wires on the 3D breadboard.
- Microcontroller emulation and more Arduino libraries.
- Guided worksheets with a challenge, solution and assessment criteria.
- Impeca accounts to save online and share circuits.
- Classrooms for schools: assignments and progress by group.
- ESP32 and Wi-Fi.
How it works
Four steps, from the example to your working circuit.
- 1 Pick an example Start with the blinking LED, the traffic light or the voltmeter, or with a blank sketch.
- 2 Check the circuit Every component has its pin: change it, add more parts and watch the wires follow to the board.
- 3 Write and run Change the code, press Run and watch. Press the button or move the sliders to test the inputs. The console shows what your sketch prints.
- 4 Take it to the real circuit Download the code as .ino, open it in the Arduino IDE and build the circuit with your kit.
What you can practise today
The same topics as Impeca Tech’s books and projects, ready to try.
Sensors
Light and temperature: measure the environment and react in code.
Servos
Move a mechanism and control its position.
Screens and data
Show values on an LCD screen and in the serial console.
Programming
Variables, loops, functions, arrays and conditions, with the UNO’s integer sizes.
Mini projects
Traffic light, night light, thermometer with alarm, reaction test.
Your Impeca account
Today your work is saved in this browser. With your Impeca account you will be able to save it online and pick it up from any device: we are preparing it.
- Save your circuits online and pick them up whenever you want
- Track your progress by project and by level
- Share a circuit with your teacher or your team
- Buy books and templates with the same account
Questions about Impeca Lab
Do I need to install anything?
No. It runs in your computer or tablet browser (recent versions of Chrome, Edge, Firefox or Safari).
Does the 3D view work on my device?
It works in current computer, tablet and phone browsers that support WebGL. If yours does not, or you prefer something simpler, use the 2D / 3D switch: the 2D view does the same. The 3D view only redraws when something changes, to save battery.
Is it a real simulator?
It is our own interpreter of the Arduino language with a virtual UNO board. It is good for learning the logic, testing code and watching the circuit react. It does not emulate the chip yet: timings are approximate and some libraries are missing. That emulation comes in a later phase.
What does it understand of the Arduino language?
Variables with the UNO’s sizes, arrays, functions, if/for/while/switch, #define, Serial, Servo and LiquidCrystal, and the usual functions (pinMode, digitalWrite, analogRead, delay, millis, tone, map, random…). If you use something that does not exist yet, the lab tells you with a clear message.
Does it replace the physical kit?
No: it is the step before. You practise risk-free and, when you are ready, build the real circuit with your kit.
Where is my work saved?
In this browser on this device. Download the code as .ino to keep it: if you clear the browser data, it is lost. Saving online with your Impeca account is being prepared.
Is it useful for classes and schools?
Yes, for practising in class: each student opens the page and picks an example. Classrooms with assignments and group progress are being prepared; write to us if you would like to run a pilot.
Try the lab now
Open the test bench, pick an example and press Run.