ArduinoStudio Bridge

The Bridge is a lightweight desktop app that connects your browser to your Arduino board over USB.

Why Do I Need the Bridge?

On Chrome, Edge and Opera on desktop, and on Chromebooks, the editor can reach your board without the Bridge. Click USB direct in the toolbar, and in Connect to hardware click Connect on the USB direct row. That path uses the browser’s Web Serial support.

You need the Bridge in two cases:

• Your browser has no Web Serial, such as Firefox or Safari. Start the Bridge, then use the Browser-agnostic — for Firefox/Safari/etc. row in Connect to hardware.
• Your project uses a block that USB direct can’t run yet. Play then shows “USB direct does not support … yet” and does not run the sequence on your board. If the block is in the first list below, connect through the Bridge instead. Blocks in the second list don’t work properly on a real board yet, so the Bridge won’t help with those.

The Bridge runs quietly in your system tray and acts as a relay: it receives commands from the editor and sends them to your Arduino over USB using the Firmata protocol.

Blocks that need the Bridge on a real board

USB direct runs the Standard LED, Servo, Button, Photoresistor, Switch and Potentiometer blocks, plus Wait, Loop and Check, with nothing installed. These blocks run on a real board only through the Bridge:

• RGB LED
• DC motor
• Relay Limited A Relay block drives its pin LOW; only pressing Stop drives it HIGH again.
• Piezo buzzer
• Proximity sensor
• Thermometer
• Barometer Limited Takes one reading and skips the block right after it. Nothing is shown and no block can use the reading.
• Accelerometer
• IMU Limited Takes one reading from an MPU6050 and skips the block right after it. Nothing is shown and no block can use the reading.
• Compass Limited Takes one heading reading and skips the block right after it. Nothing is shown and no block can use the reading.

These blocks don’t work properly on a real board yet, over USB direct or through the Bridge:

• ESC Not working yet At a Speed of 40% or more it sends the minimum throttle signal, so the motor will not spin at the default.
• IR motion sensor Not working yet Listens on digital pin 0 instead of the Analog pin, so a sensor wired to A0 never triggers it.
• Joystick Not working yet Carries on as soon as the joystick sends its first reading, without waiting for the stick to move. The position cannot be used yet.
• Hygrometer Not working yet Its fixed DHT11 setting is not a sensor the Bridge can drive, so the run stops without a reading.
• Gyro Not working yet Its fixed ITG3200 setting is not a sensor the Bridge can drive, so the run stops without a reading.

Download

Download the Bridge for your platform from the download page.

Installation

Windows

Run the .exe installer. It installs and launches automatically in your system tray. If Windows SmartScreen appears, click “More info” then “Run anyway” — this happens because the app isn’t code-signed yet.

macOS

Open the .dmg file and drag ArduinoStudio Bridge to your Applications folder. On first launch, right-click the app and select “Open” if Gatekeeper blocks it.

Linux

sudo dpkg -i arduinostudio-bridge_*.deb

How It Works

1. The Bridge starts a local WebSocket server on localhost:7545
2. The editor at app.arduinostudio.com connects to this WebSocket
3. The Bridge detects Arduino boards connected via USB
4. When you press Play, commands flow: Browser → Bridge → Arduino
5. Sensor data flows back: Arduino → Bridge → Browser

Firmata

ArduinoStudio uses the Firmata protocol to communicate with your Arduino in real time. New boards don’t come with Firmata. The first time you connect a board through the Bridge, the setup wizard flashes Firmata firmware onto it. You only need to do this once per board. (Over USB direct, the wizard uploads it from the browser on an Uno, Nano or Mega.)

Firmata replaces whatever sketch was previously on the board. If you want to go back to the Arduino IDE later, just upload any sketch normally — it will overwrite Firmata.

Troubleshooting

Bridge not detected

• Make sure the Bridge icon appears in your system tray (Windows) or menu bar (macOS)
• Try restarting the Bridge
• Check that no firewall is blocking localhost:7545

Arduino not detected

• Try a different USB cable (some cables are charge-only, no data)
• Try a different USB port
• On Linux, make sure your user is in the dialout group: sudo usermod -aG dialout $USER
• Check Device Manager (Windows) or ls /dev/tty* (macOS/Linux) to verify the board is recognized by the OS

Firmata flash failed

• Make sure no other program (Arduino IDE, serial monitor) is using the port
• Disconnect and reconnect the Arduino, then try again
• Select the correct board model in the setup wizard

Auto-Updates

On Windows and macOS, the Bridge automatically checks for updates every hour and installs them in the background. You’ll see a notification in the tray when an update is ready — click “Restart to Update” to apply it.

On Linux, download the latest .deb from the download page and reinstall.

See the editor in action with a guided demo, no account or install needed: open the demo