Using a Gamepad

Using Gamepads

While our robot is able to do a lot autonomously, more often than not we need, or want, to input commands using a gamepad. There is a wide variety of gamepads that are compatible with the Driver Hub. For this tutorial we will be focusing on a generic PS4 controller, such as the, REV USB PS4 Compatible Gamepad, or an Etpark Wired Controller.

To initialize the gamepad that will act as User 1 (gamepad1, in code) press the options button and the Cross/A button on the gamepad at the same time. To initialize User 2 ( gamepad2, in code) press the options button and the Circle/B button at the same time.

All buttons on a gamepad can be programmed to a specific task or behavior. Let's take a look at the breakdown of each button, their associated block name, and the type of data they output:

PS4 Controllers	Generic USB Gamepad	Blocks	Data Type
Cross	a		Boolean
Circle	b		Boolean
Triangle	y		Boolean
Square	x		Boolean
Dpad Up	Dpad Up		Boolean
Dpad Down	Dpad Down		Boolean
Dpad Left	Dpad Left		Boolean
Dpad Right	Dpad Right		Boolean
Left Bumper	Left Bumper		Boolean
Right Bumper	Right Bumper		Boolean
Left Trigger	Left Trigger		Float
Right Trigger	Right Trigger		Float
PS	Home		Boolean
Options	Start/Options		Boolean
Share	Back/Share		Boolean
Left Stick Button	Left Stick Button		Boolean
Left Stick X Axis	Left Stick X Axis		Float
Left Stick Y Axis	Left Stick Y Axis		Float
Right Stick Button	Right Stick Button		Boolean
Right Stick X Axis	Right Stick X Axis		Float
Right Stick Y Axis	Right Stick Y Axis		Float

Boolean vs Float Data Types

The gamepad outputs two types of data back to the Control Hub to be used within the program:

Boolean

Boolean data has two possible values: True and False. These two values can also be represented by On and Off or 1 and 0.

The buttons, bumpers, and triggers on the gamepad provide boolean data to our robot! For example, a button that is not pressed will return a value of False (or 0) and a button that is pressed will return the value True (or 1).

Float

Float data is a number that can include decimal places and positive or negative values.

On the gamepad, the float data returned will be between 1 and -1 for the joystick's position on each axis. Some examples of possible values are 0.44, 0, -0.29, or -1.