Ever wanted to make a arduino shield in this instructable is your guide to make a shield with two features and it is a cheaper alternative for the real one . This shield works on IC l278 and Hc 05 combined . This shield can be used to controls motors, toys, etc wireless. The shield can control up to two 24V motors and the wireless functions on Bluetooth you can use a serial monitor on your computer to check out its working. I have several projects using this shield and have no problem with it. It als can work with pmw so you can set speed values, through serial data transfer.
Step 1: Motor H bridge
IC l298 is used to control the motor part of the circuit The output 1&2 goes to the left motor and 3and4 goes to the right . Similarly the inputs 1and 2 is to control the left motor and 3and 4 is to control the right motor .
As for the inputs should be connected to arduino digital pins go for alternate pins like 2and4 and leave pin 3 for the enable pin. For forward motion set input pin 1and3 high and the others as low also set enable pins as high . Do just the reverse of it for back motion .
Enable pin will set the state and speed of the motors connect it to pin 3and5 . Always set the enable pin to high to get the motors running.
To see an example of how to get the motors going and code check my other instructables