Roughly the size of a Tic Tac container, this project packs a punch in a compact package. [Matt] sent in this beautifully documented pocket device that brings back great memories of texting on early cellphones.
The EclairM0’s firmware is written in TinyGo, a language he hadn’t used before but found perfect for a microcontroller project where storage space is tight. The 14-button input mimics early phone keypads, using multi-tapping and combo key presses to offer various functions. The small SSD1306 OLED display is another highlight. Building on an earlier CircuitPython project, [Matt] optimized the screen’s performance, speeding up its response time for a snappy user experience. The battery picked was only 3 mm thick, however the protection circuity on the battery added another 2 mm so he moved that protection circuity to the main PCB itself to keep it as thin as initially planned.
Weighing just 15 grams, this lightweight device runs on a SAMD21 microcontroller, which supports USB host functionality. This allows the EclairM0 to act as a keyboard, mouse, or even USB peripherals. Housed in a 3D-printed case, the entire project is open-source, with design and firmware files available on GitHub.
We love small handheld projects around here and this well-documented, fun pocket device is no exception, if you want your own he has a page dedicated to helping you build a EclairM0.
I’m impressed by the elegant design of it. I would probably like some indication of special functions on the keyboard, because I would quickly forget which combo did what.
I am fascinated by these types of pocket notepads, as well as the “pure typing machines” I’ve seen on HaD, but I can’t imagine integrating them into my EDC kit. I already carry way too many gadgets in my pockets. Adding another one would be too much.
Isn’t USB device functionality required to act as keyboards or mice? And doesn’t “or even” imply that keyboard and mouse aren’t USB peripherals?
I think the author meant USB device functionality. The USB host is the computer you’re plugging into. Indeed, the keyboard, mouse, or mass storage (what they call bootloader/DFU) are all USB device class supported by the SAMD21 microcontroller.
Exactly! I’ll work to clarify/communicate that better in the future.
That’s got to be the strangest tiny keyboard I’ve ever seen, but it looks surprisingly useful.
This tiny device is really cool. I don’t know if I love or hate the keyboard layout. I have QWERTY memorized but not telephone keypad letters so maybe it’s not bad. I adore the USB functionality