Why you need a controller
In this tutorial, we used a motor driver board to interface our micro:bit with two motors—but why did we need that controller? The controller is simply there to buffer the micro:bit as motors require a considerable amount of current in order for them to start moving.
This is current that the micro:bit is unable to provide without potentially damaging the unit. We used a Kitronik motor driver board, but at its heart is a DRV8833 motor controller that uses an H bridge or ‘flip flop’ circuit to control the direction of the current. Remember in the tutorial we changed the polarity of the motors to change direction? Well, that’s the H bridge circuit in operation.
But do you need to buy the Kitronik kit? You can make your own by buying a motor control board, such as the DRV8833, L293D or the L9110S, and all of them are compatible with the micro:bit but you will need to break out more GPIO pins from the micro:bit as the three provided aren’t enough.
You can purchase adaptors that convert the edge connector of the micro:bit for use with breadboards and common electronics, reducing the cost of your robot builds and enabling you to build multiple robots for your new army!