Arduino Uno with Built-in Wifi : MQTT Username too long

I am using an Arduino Uno with built-in WiFi :

(i.e. not with a separate ESP8266 or with a WiFi shield).

I'd like to connect to a server via MQTT. In order to do so, I knwo that I need to configure the MQTT settings (Server Hotname, Server Port, Client ID, Username, Password) via my browser specifying the local IP Address of my arduino Uno, under the "Connectivity" settings.

The username for the MQTT Server is 36 characters long. The password is 40 characters long.

I get an error for both:

  • Apparently the Arduino Uno with Built-In WiFi only accepts 31 characters : "Error: Value for mqtt-username too long (36 > 31 allowed)"
  • The Password also seems to be limited to max 31 characters by my Arduino Uno with Built-In WiFi: "Error: Value for mqtt-password too long (40 > 31 allowed)"

Any help would be appreciated !!!

Many thanks !


change the firmware. use esp-link or WiFi Link. esp-link has MQTT support. WiFi Link’s atmel side library is similar to WiFi or Ethernet library.

Uno WiFi & WiFi Link unofficial documentation

Thanks. However the procedure described on the page is hardly understandable :frowning: I am not sure if everything on this page is a set of different options, or a long list of mandatory tasks. Is there any link you could recommend ?

It is a long list of options. First you must decide what firmware you want use. If WiFi Link, then start with flashing the release binaries. If successful it may be all you need. If you want a 1.0.1 version the continue with uploading from source code. I you want sketch OTA upload then use the ota branch source code. ...

btw: I am the author of the doc :slight_smile: