Setting Up Your Adapter

This guide walks through a complete first-time setup.

Physical connection#

1. Console — Insert your game cartridge and power on the console.
2. Link cable — Connect one end to the console’s link port and the other to the GB-Link adapter.
3. USB — Connect the adapter to your computer or Android phone with a USB cable.

GBA cable orientation#

GBA link cables have two different connectors:

• Slim connector = Master
• Wide connector = Slave

The GB-Link adapter must be connected to the master (slim) connector for GBA modes.

Tip: Connect the cable to the adapter before selecting a GBA mode in the web app. The firmware detects the cable type at mode selection time.

Browser connection#

Open launcher.gblink.io and plug your adapter into USB if it is not already connected.

On the launcher (before you connect)#

Scroll to the Device Health panel (right side on desktop, below the game list on mobile). You should see:

• The heading Device Health
• The line: Connect your GB-Link adapter to upgrade and configure your adapter.
• A blue Connect button

Click Connect. Your browser will open its own permission UI — the steps below depend on which browser you use.

After a successful connection#

The Device Health panel switches from the Connect button to a details view:

The page footer should show something like WebUSB: WebUSB · Browser: Google Chrome. The adapter LED should turn green.

Google Chrome (desktop)#

1. Click Connect in Device Health.
2. Chrome opens a centered modal at the top of the window:
   • Title: launcher.gblink.io wants to connect to a USB device
   • Body: a list of USB devices (one row each)
3. Click the row for your adapter to select it.
   • Current GB-Link firmware usually shows as Game Boy Link.
   • Older boards may show a different name (vendor cafe or 239a).
   • If you are in BOOTSEL update mode, you may see RP2 Boot instead.
4. Click the blue Connect button at the bottom of the modal.
   • Do not click Cancel — that closes the dialog without connecting.
   • Connect stays greyed out until you select a device in the list.

If the list is empty or says No compatible devices found, the Connect button in the modal stays disabled. Check that the adapter LED is on, try another USB port, or see Linux permissions below.

If you closed the modal, click Connect on the launcher again — the browser only shows the picker after you click that button.

Optional plug-in shortcut: If Open the launcher automatically when this adapter is plugged in is enabled on your adapter, Chrome may show a system notification when you plug in USB. Click the notification to open the launcher, then click Connect and complete the steps above.

Microsoft Edge (desktop)#

Same modal as Chrome:

1. Click Connect on the launcher.
2. Modal title: launcher.gblink.io wants to connect to a USB device
3. Select your adapter in the list → click Connect (not Cancel).

Other Chromium browsers (Brave, Opera, Vivaldi)#

Same as Chrome — look for the wants to connect to a USB device modal, select your adapter, click Connect.

Mozilla Firefox (desktop, 151+)#

Firefox uses WebSerial, not WebUSB. After you click Connect in Device Health, you go through up to three prompts.

Step A — Install serial access (first visit only)#

Firefox asks permission to install a small add-on so the site can use serial ports. You only see this once per Firefox profile.

1. Click Continue to Installation (not Don’t Allow).

2. On the add-on dialog, click Add (not Cancel).

Return visits skip steps A and go straight to the port picker below.

Step B — Select your adapter#

1. Click Connect on the launcher (if you have not already).
2. In the popup titled Allow launcher.gblink.io to access your serial ports?, open the Select a serial port: dropdown.
3. Choose GBLink USB (or your adapter’s entry — often the only option).
4. Click Allow (not Block).

If the dropdown says No serial ports available, replug the adapter and click Connect again.

Success on Firefox#

Device Health should show:

• Status: Connected (WebSerial)
• A note: Connected over WebSerial — firmware flashing is manual…

One-click Update firmware requires Chrome or Edge. On Firefox, expand Flash manually instead and use Download firmware (.uf2) if you need to update.

Chrome on Android#

1. Connect the adapter with a USB OTG adapter or cable.
2. If Android shows a system prompt (e.g. Allow Chrome to access USB device?), tap OK or Allow.
3. Open launcher.gblink.io in Chrome and tap Connect in Device Health.
4. The same modal appears: launcher.gblink.io wants to connect to a USB device
5. Tap your adapter in the list, then tap Connect.

If the list is empty, check OTG is enabled in your phone settings and try replugging the cable.

Not supported#

Game cards on the launcher page still open, but Device Health cannot connect the adapter. Use Chrome or Edge on desktop, or Chrome on Android.

Verify the connection#

In Device Health you should see:

• Status: Connected or Connected (WebSerial)
• Firmware: a version number (not Unknown)
• USB ID: a code like 2fe3:0003

The page footer should show your browser name and WebUSB: WebUSB (or WebSerial (fallback) on Firefox).

If connection fails, click Connect again, try another USB port, or unplug and replug the adapter.

Linux permissions#

On Linux, browsers need permission to access USB devices. Run this once from the firmware repository:

./scripts/setup-permissions.sh

This installs udev rules for both WebUSB and WebSerial.

Customize your adapter#

From the launcher you can:

• Update firmware
• Change per-mode LED colors
• Set whether the browser opens the launcher automatically on connect

See Updating Firmware and LED Status Indicators for details.