Beetle-A Small Microcontroller for Arduino Leonardo with USB HID for IoT & Wearable Projects (20mm×22mm, ATmega32u4, 3V Battery Support)

Works like a charm -- and given the size, charm is a good word. In the attached photo, if you can even see the Beetle, compare it to the size of a USB connector or alligator clip.If the pinout is enough for your project, the size is quite appealing. In the toy I'm making, the LiPo battery is bigger than the PowerBoost 500 charger, which is bigger than the Beetle, so everything snuggles nicely in a small space.Arduino compatible, just select Leonardo as the board type in the IDE.

Made my smallest K3NG, using the Beetle as its heart. I only had to change which pins were input/output and nothing else in the code for the upload to take and work first shot. It doesn't have as much memory space as a full Arduino Nano, but the SDA and SCL pins are better marked, as are the VCC and GND pads. The pads are big, and easy to solder, overall even better than the old Digispark boards.

I understand to make the board small they did not put a reset button. So warning. do not write a sketch that disables interrupts because you'll brick the board.

It's tiny, it's inexpensive, and it works with the Sketch I made with an actual Leonardo. I keep it stored in a case meant for earplugs when not in use. Arduino IDE sees it as a Leonardo, everything works as a Leonardo.Splendid

I love the PCB design. It gives an amazing variability to installation.I am not happy about having to reset the PC interface every third connection. (Leonardo issue)The pins are just what you need for a compact project. The PCB only has pads for 3 digital and 3 analog, or 6 digital. If you need more than that you need a different chip with more memory. The duel set of power pads is very handy. Communications pins are easy to solder to.Over all, very nice device. I will buy more.

This thing is hot garbage. Can't flash it no matter what I do. It's recognized by the Arduino IDE but won't flash it, neither will avrdude command line nor dfu-programmer. The documentation is also horrible and tells you to short "pins 5 and 6" on the ICSP, but they're not labelled on the board or the wiki. I think I figured out which pins they are, and it looks like it's resetting and/or entering DFU mode, but it still won't flash. The IDE attempts it then throws a ton of different errors. It's just not worth the aggravation.

As someone trying to use it for a Cosplay, I can't fathom the design choice to not have at least 1 digital pin interrupt. This is a standard feature that this device lacks. Timer based interrupts are terrible for power consumption and force you to rely on polling for checking a button's status. This would easily be a 5 star product if not for this glaring oversight.

I bought a couple of these for a mini device I was building for fun. It is so small and cute and works perfectly with Arduino code, just upload and go! It also powers perfectly from any USB 5V phone battery pack! The device I built is proprietary, but dealt with converting stings of data into wireless signals! These little things worked perfectly and so well priced for it's ability!