Stylised error 404 graphic over scrolling binary code, illustrating amomii Link troubleshooting and error codes

amomii Link: Troubleshooting & Error Codes

by Shaun Armstrong in amomii Link

Successfully flashing your hardware should feel like magic, but sometimes the "tech spirits" don't cooperate. If you’ve encountered an error code in the amomii Link tool, don’t worry—most fixes take less than 60 seconds.

Step 0: Compatibility Check

Before looking up your error code, ensure you are using a compatible browser. amomii Link requires Web Serial technology, which is currently supported by:

  • ✅ Google Chrome (Desktop & Android)

  • ✅ Microsoft Edge (Desktop)

  • ✅ Opera (Desktop)

❌ Currently Incompatible: Safari and Firefox do not support this technology yet. If you are on an iPhone or iPad, please switch to a computer or an Android device.

Find your error code below to get back to the party!

ERR-101: Data Fetch Error

What it means: The tool couldn't download the project code from our servers.

  • Check your Internet: Ensure you have a stable connection.

  • Refresh the Page: Sometimes a simple refresh clears a temporary handshake issue.

  • Browser Extensions: Some "Ad-Blockers" or aggressive security extensions can block the data transfer. Try disabling them for this site.

ERR-202: Device Not Found

What it means: The browser sent out a search party, but your amomii or Arduino board didn't answer.

  • The Cable Check: This is the #1 cause! Ensure you are using a Data Sync USB cable. Many cheap cables are "Charge Only" and cannot send data. Learn more about USB cables here.

  • The Port Check: Unplug the USB from your computer and plug it back in (try a different port if available).

  • Connection State: Ensure your amomii board is powered on and the status lights are visible.

ERR-303: Security or Port Busy

What it means: Something else is "locking" the connection to your board.

  • Close Other Tabs: If you have another amomii Link tab open, or an online Arduino IDE open, close them. Only one tab can talk to the hardware at a time.

  • Permission Denied: When the browser popup appeared, did you click "Cancel"? Refresh the page and make sure to select your device and click Connect.

ERR-999: Unknown Glitch

What it means: A general error occurred during the upload process.

  • Use "Stable Mode": In the amomii Link tool, change the Upload Stability dropdown to "Stable Mode (100ms)". This slows the data down and makes it much more reliable on older computers or longer cables.

  • Check Your Browser: Double-check that you aren't accidentally using Safari or Firefox (see the Compatibility Check at the top).

Still Stuck?

If you have tried the steps above and your board still won't activate, we are here to help! To help us fix this for you quickly, please send an email to support@amomii.com including the following:

  1. The Error Code you saw (e.g., ERR-202).

  2. Your Setup: Are you on a PC, Mac, or Android?

  3. The Steps You Tried: For example: "I tried a different cable and used Stable Mode, but it still didn't work."

We'll get you back to hacking in no time!

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