Setting Up L298n H-Bridge
This tutorial assumes only a single combined speed control for both motors. For independent speed of each motor the tutorial will be slightly different - See post #2 of this topic.










Assuming ports D15, D16, D17, D18 & D19
D15 Signal > Left Trigger A (In 1)
D16 Signal > Left Trigger B (In 2)
D17 Signal > Right Trigger A (In 3)
D18 Signal > Right Trigger B (In 4)

D19 VCC > H-Bridge 5V
D19 Ground > H-Bridge Ground
D19 Signal > H-Bridge ENA & ENB


D19 Signal will need to be connected to 2 pins on the H-Bridge and the jumpers on the H-Bridge removed. I made a Y cable out of a couple of jumper cables.

Connect the positive of the battery to the H-Bridge VCC

Connect motor 1 to the Out 1 and Out 2 terminals
Connect motor 2 to the Out 3 and Out 4 terminals

In ARC add a 4 Wire H-Bridge control and a PWM control.

Set up the H-Bridge control as the above D15 to D18 on LTA, LTB, RTA and RTB
Set up the PWM control to D19

To use, set the PWM to 100% (or a lower value if you want it slower) - I have mine set to 100% in an init script that is run on successful connection of the EZ-B.
Use the H-Bridge control and the motors should move.

Here is a project with both controls added, you can save it and merge it with your project (or open it and test the H-Bridge). It's also accessible in ARC by opening from the cloud.

Note:
The PWM wire is optional. If you wanted to save a digital port and lose speed control you could connect any of D15 to D18's VCC to the H-Bridge 5V and any of the D15 to D18's Ground to the H-Bridge Ground. Keep the jumpers on between ENA and 5v and ENB and 5v.


If your H-Bridge looks different, they are pretty much all much of a muchness. A H-Bridge generally has 4 inputs to control the 2 motors plus 1 or 2 inputs for speed control. The same principle as above can be applied.

Signal wires from Digital ports to each of the inputs to control the motors. Generally labeled In1 to In4 or AIn1, AIn2, BIn1 and BIn2.
Signal wires (this can be combined for 1 port if you don't want individual speed control from side to side) for the PWM or speed. Generally labelled as ENa and ENb.
+5V or VIn is generally the 5V from the EZ-B
Vm is generally the supply to the motors taken from the battery.
Ground is always Ground, taken from any ground since it's a common ground.


A simple truth table for how the H-Bridge works.

Code:

 In4 | In3 | In2 | In1 | Function
-----+-----+-----+-----+--------------
  0  |  0  |  0  |  0  | Stop/Free Wheel
  0  |  0  |  0  |  1  | Motor 1 Forward
  0  |  0  |  1  |  0  | Motor 1 Reverse
  0  |  0  |  1  |  1  | Motor 1 Brake
  0  |  1  |  0  |  0  | Motor 2 Forward
  1  |  0  |  0  |  0  | Motor 2 Reverse
  1  |  1  |  0  |  0  | Motor 2 Brake

 In4 | In3 | In2 | In1 | Function
-----+-----+-----+-----+--------------
  0  |  1  |  0  |  1  | Robot Forward
  1  |  0  |  1  |  0  | Robot Reverse
  1  |  0  |  0  |  1  | Robot Turn Left (or right depending on motor orientation)
  0  |  1  |  1  |  0  | Robot Turn Right (or left depending on motor orientation)
  0  |  0  |  0  |  0  | Robot Stop