Reddit user [nomoreimfull] Post code for Dynamic Wi-Fi beacon to r/arduino. The simple, yet clever graphic is pre-loaded with some fairly familiar song lyrics and is made to rick roll Wireless LAN users via broadcast ESP32 WiFi Radio SSID (Service Set Identifier).

The ESP32 and its younger brother, the ESP8266, are microcontrollers that feature built-in WiFi support. With its small size, price, and power-saving characteristics, it has become a favorite of makers, hackers, and yes-phishers for a wide variety of projects. It can be easily programmed using its own SDK or through the “board support” extension to the Arduino IDE.

For a dynamic WiFi beacon, the ESP32 is put into AP (Access Point) mode and broadcasts the human-readable name (SSID) as configured. What makes an SSID dynamic, or rolling, is that the scheme periodically updates the SSID to the next line of text stored within the code. Of course, in the Rickroll prank that means the next line from the lyrics to “Never Gonna Give You Up” by Rick Astley himself.

Always a favorite joke, we’ve seen Rickrolls take the form of infrared remotes, free WiFi servers, and tossing coin cells.

Photo by Rick Astley: Wjack12, CC BY-SA 4.0.1 Update.