How to Display a QR Code

By mvuilleu, in Programming and New stuff, october 23,2026.

QR codes are often used for advertising purposes to share website addresses on posters or flyers. They can also convey other types of information, such as Wi-Fi settings, a vCard, or a GPS location. If you can generate them dynamically, you could even create a time-limited code, or a proof-of-time stamp... and that's where it gets really interesting.

A small and very unobtrusive display

By martinm, in DIY and Programming, october 16,2026.

For an in-house project, we needed a small display that we could read from a few meters away, even in the dark, but that would remain unobtrusive when not in use. We were therefore very tempted by these displays that remain invisible when turned off, which is why we decided to use a 15x7 CharliePlex LED Matrix Display FeatherWing from Adafruit, driven by a Yocto-I2C-C, all enclosed in a 3D-printed plastic case.

Google Calendar on your Yocto-Display-ePaper-C

By seb, in DIY, october 11,2026.

Twelve years ago, we built a DIY project that displayed upcoming events from a Google Calendar on a Yocto-MaxiDisplay that was built into a kitchen cabinet. This week, we're going to update this setup so that it uses our new Yocto-Display-ePaper-C module and shows the events on an ePaper display. We'll also take this opportunity to simplify the code and get rid of the OAuth2 authentication system.

A Yoctopuce time clock

By Tiago, in DIY, october 02,2026.

A while back, the Commission de l'inspection paritaire des entreprises (Joint Labor Inspection Commission) for the Canton of Geneva issued us a formal notice requiring us to implement a system for tracking work hours for all staff. Until now, Yoctopuce had operated on a trust-based system, and that had never caused the slightest problem. But hey, the law is the law, so we had no choice but to comply :( So, since we had to track work hours anyway, we figured we might as well do it the Yoctopuce way :)

Uploading firmware with XMODEM/YMODEM

By mvuilleu, in Programming, september 25,2026.

XMODEM and YMODEM are protocols that enable reliable file transfers over a serial connection (UART). They were designed 50 years ago to improve the reliability of data transfers over analog telephone lines, and one might have expected them to have disappeared completely by now. However, there are still a few specific cases where they are widely used, which is why we have just added native support for these protocols in our serial communication modules.