This Laser-Cut Raspberry Pi Media Control System Offers Simple Yet Powerful Fingertip Control

Semi-anonymous maker "Martin" has put together a macro pad with a difference, building an attractive media control system built right into a desk and with laser-etched labels for ease of use.

"[I] put some leftover Gateron Silent and Gateron Brown [mechanical keyboard switches] into a board I made with the laser cutter," Martin explains of the project. "The keys are connected directly to a Raspberry Pi GPIO [General-Purpose Input/Output header], which runs a 'Logitech Media Server' and also doubles as a radio itself. Since the [Raspberry Pi] had no buttons for control and I did not always want to control on the PC or smartphone, an offline interface had to be made. I am very satisfied with it."

The heart of the project, as Martin explains, is a Raspberry Pi 3 Model B single-board computer, wired directly to the eight Cherry-compatible mechanical keyboard switches without the need for passive components like diodes or resistors. Jumper cables were soldered to the switches, then slotted onto the Raspberry Pi's GPIO header — one pin per switch, with a common connection to the 3.3V pin.

"On the Raspberry Pi, DietPi [operating system] is used," Martin adds. "This works great for my applications and is more intuitive for me to use than e.g. Raspian. [I also used] Logitech Media Server (LMS), SqueezeLite, Python 3, [and my] own code."

That code listens out for activity on the GPIO-connected switches and triggers shell scripts which send instructions to the the media server. There are buttons for pausing and resuming playback, increasing and decreasing volume, skipping songs, opening the playlist, and selecting songs — all labelled using a piece of laser-etched wood screwed into a hole cut into the desk, providing room for the electronics underneath.

"[It's] a 40W DIY CO₂ laser," Martin writes of the laser cutter used in the project. "[It] works very reliably and well. But I no longer want him in the living room and don't have a place in another room for it, so a friend gets him as a gift, she is also artistically much more talented than I am."

Martin has published full instructions for the build, along with downloadable source code and design files for the laser-cut wood, on Medium; more information is available on Martin's Reddit thread.