UDP Broadcasting And Easily Finding Network Services

July 1, 2026 by Maya Posch 25 Comments

Local area networks (LANs) that use technologies like Ethernet and Wi-Fi are incredibly useful for letting devices talk with each other. Yet a core problem here is knowing which devices are where on the network, as anyone who has ever tried to add a network printer or network share to their system can probably attest to. Unless you happen to know the IP address of the LAN device, the port, and protocol, the target device may as well be located on the Moon without further help, such as automatic network discovery in lieu of waddling over to the device and reading the label listing its IP address.

Over the decades quite a few ways have been developed to enable such network discovery, with many of them using UDP broadcast as the first step. By broadcasting a global message on the entire LAN, any device that has an actively listening UDP socket on that particular port can parse said message and decide whether it’s feeling sociable enough to reply.

The topic of UDP broadcasting is however not as straightforward as it may sound if you’re just getting started, including the existence of many opinions on the ‘right way’. There is also a massive divide between a sprawling service discovery protocol like mDNS and a light-weight one like that one that I had to implement a few years ago for an open source project.

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Terminus Is A Text Only Phone Because Telephony Is Dead Anyway

July 1, 2026 by Tyler August 17 Comments

This may say more about us than the current state of the telephone network, but unless your Grandma is still kicking, how many phone calls do you take that are actually worth picking up? Around here it’s one variety of scam or another, with the odd cold-calling salesperson to round it out.

So when we saw [Bolan Xu]’s texting-only TERMINUS cell phone project, it took but a minute to decide that, yeah, we wouldn’t miss the telephone part of the phone very much either.

The trade-offs are immense when compared to your smartphone; there’s no voice, no web browser, no social media, and no camera. But on the flip side there’s also no spyware and no annoying spam calls. Besides, he’s built a QWERTY keyboard onto this thing, and that does seem to be what most of us miss in this era of black rectangles.

In terms of electronics, its rocking a tiny OLED display for you to read your messages on, driven by an ESP8266. When WiFi is available the plan was to bridge over the internet in an SMS version of VOIP, but [Bolan Xu] ended up installing a cellular modem in it anyway.

As you can tell from the skeletal case, this is very much a prototype, but it is a promising project. We’ve seen ESP-based phones before, but they tend to be a bit smarter, and run on ESP32 instead of the more modest ESP8266.

Watch A Steam Controller Skitter Itself To Its Charge Puck

July 1, 2026 by Donald Papp 12 Comments

Hacks don’t have to be practical but it helps if they are educational or clever or amusing, as [Ray Foss] demonstrates with his auto-docking Steam Controller.

It’s an open-source web application that combines a camera, a Steam Controller, and some clever software for the sole purpose of saving the user from the tyranny of having to manually set the controller onto its magnetic charging puck. Instead, one can simply lay the controller down nearby and let the computer do the rest of the work.

First one fires up the web interface, ensures a webcam has a good top-down view of both the charging puck and the controller, connects wirelessly to the controller, then clicks a few points on the camera view to tell the system where things are.

After that, the system buzzes the controller’s haptic feedback motors to make it skitter across the desktop until — guided by the camera and implementing obstacle avoidance — it docks successfully with its magnetic charging puck.

It may not be super practical and may even seem a bit Rube Goldberg-esque, but it’s fun and demonstrates a few interesting things. One is moving a controller via slip-stick friction by asymmetrically pulsing the feedback motors. Another is automatically reducing the pulse frequency to make smaller movements when it gets close to the charging puck, for finer control.

The computer vision part also ignores anything in expected cable locations, removing the need to deal with them algorithmically. WebHID via the browser takes care of talking to the controller, and confirming a successful docking by watching messages to detect when charging has begun.

If this seems a bit familiar, it’s because this project was inspired by the work of [Very Lazy Pixels] which we covered previously.