Can I Get Your Number?
This USB dongle uses an RP2350 to automatically retrieve and display the IP address of a headless Raspberry Pi when plugged in.
Sometimes it’s the little things in life that matter the most. And if you happen to have a stack of headless Raspberry Pis in a corner of your homelab, GitHub user C4KEW4LK’s IP address-revealing USB dongle could matter a lot to you. It is common for Raspberry Pis to run applications that automate one’s home or serve up web content for years without any attention. Then one day, you might find that you need to ssh into one of them to fix something. But wait… what was its IP address again?
If you don’t have the discipline to slap a label on everything, then C4KEW4LK’s device can bail you out. It is a small Raspberry Pi RP2350-based development board paired with a tiny Waveshare 1.47-inch LCD module. This hardware is installed in a 3D-printed shell to make the dongle look finished.
When plugged into a Raspberry Pi’s USB port, the device automatically runs a few commands to grab some network information. First, it acts as an HID device to send the host a Ctrl+Alt+T keyboard combination, which opens a terminal. Next, the `hostname` and `ip` commands are executed. The results are parsed and displayed on the device’s screen.
C4KEW4LK wrote a small Arduino sketch to make all of this work, and the source code is available on GitHub if you want to try it out for yourself. Nothing needs to be installed on the host machines.
So far, the dongle has only been tested on Raspberry Pi OS Trixie. However, since the method it uses is pretty generic, it will likely run on many other operating system versions as well. There is a good chance it would even work on other single-board computers aside from Raspberry Pis.