The BBC micro:bit is a powerful handheld, fully programmable, computer designed by the BBC. It supports the PXT graphical programming interface developed by Microsoft and can be used under Windows, MacOS, IOS, Android and many other operating systems without additional download of the compiler.
This expansion board can be connected to external power(DC 6-12V , PH2.0-2P interface) and come with a DIP switch for controlling power.
There are two groups of 4P pins extended for I2C communication interface(3.3V and 5v power supply), and another two sets of 4p pins extended for P12 and P13(3.3V and 5v power supply).