micro:bit Car with DFRobot Gamepad

What you need?

1. Arcylic car chassis with 3 wheels (kit)
2. L9110 Dual Channel Motor Driver Module
3. micro:bits x 2
4. micro:bit mate
5. micro:gamepad
6. Double sided tape to stick the battery holder to the acrylic
7. Glue gun to immobilize the back wheel
8. Dupont cables

L9110 motor driver
The HG7881 (L9110) is a compact motor driver chip that supports a voltage range from 2.5-12V at
800mA of continuous current.
Each HG7881 (L9110) chip is able to drive a single DC motor using two digital control inputs. One
input is used to select the motor direction while the other is used to control the motor speed.

Note that the actual direction of "forward" and "reverse" depends on how the motors are
mounted and wired. You can always change the direction of a motor by reversing its wiring.
The HG7881 (L9110) Dual Channel Motor Driver Module uses two of these motor driver chips. Each
driver chip is intended to drive one motor. This module can control two motors independently. Each
set of screw terminals is used to connect a motor.

Step 1 Assemble the car

Motor A Connections

** Take note of the yellow and white cable connections.
Motor B Connections

** Take note of the yellow and white cable connections.
Immobilize the back wheel by applying glue to prevent it from turning. Make sure that the back wheel is
pointing straight.

Step 2 How it works?
We are going to use the radio function to communicate between 2 micro:bits. They need to be in the
same group. When a button is pressed on the game pad, the direction is shown on the gamepad
micro:bit. A number is sent to the remote micro:bit on the car. The car will response to the different
numbers and the direction will be shown.
Step 3 Micro:bit car coding

Step4 Micro:gamepad coding

Step5 Future improvements
I can mount a missile launcher with pan and tilt servos to the car and use the x,y, A, B buttons to
control it. To fire, I can use the AB button on the gamepad.

 (this project coming your way soon.)

The original content is created by Mark Ng