This is an Arduino Development Environment Compatible Pro Micro (not Pro Mini, Pro Micro), with an ATMega 32u4 (5v, 16Mhz).
The Pro Micro is a teency weency micro controller board, barely larger than a DIP chip, it has USB built in and with appropriate programming can communicate to the computer it is plugged into acting as a USB input device (keyboard etc).
After connecting the device in the Arduino IDE select “Arduino/Genuino Micro” from the Boards menu in the Arduino IDE and choose the correct Serial port (”ACM something something”).
Check out the Examples > USB in the Arduino IDE for fun with USB keyboard and mouse input to your computer. Be sure to only use your new found super powers for good, not evil!
Note that these tend to be a bit sensitive about the USB cable, I have several micro usb cables which they just don’t like, I’m assuming that it is a voltage drop issue but have not looked too hard.
I would consider the Pro Micro an “if you have to”, personally I prefer the Nano boards with ATMega328P, but the Pro Micro allows you to do easier tricks with USB.
For information about Arduino and to download the Arduino development software see arduino.cc
