Arduino UNO R4 WiFi USB HID

In this tutorial you will learn how to emulate a mouse/keyboard using an Arduino UNO R4 WiFi board with the Keyboard and Mouse APIs.

This feature can be used to create game controllers, keyboard extensions or other HID devices.

Goals

The goals of this tutorials are:

• Learn how to emulate a keyboard (keypresses),
• learn how to emulate a mouse (x,y coordinates).

Hardware & Software Needed

• Arduino IDE (online or offline)
• Arduino UNO R4 WiFi
• UNO R4 Board Package

Human Interface Device (HID)

Human interface devices (HID) are devices designed for humans (keyboards, mice, game controllers etc.), that frequently sends data over USB to a computer. When you press a key on a keyboard, you send data to a computer, which reads it and in turn activates the corresponding key.

The UNO R4 WiFi has built-in support for HID, a feature found on most modern day development boards, but not on previous UNO revisions.

To turn your board into an HID, you can use the keyboard/mouse API that is built in to the Board Package. You can visit the documentation for this API in the language reference at:

• Keyboard
• Mouse

Sketch Upload Interference

As a consequence of the multi-processor design of the UNO R4 WiFi board, uploads may fail with a "

No device found on ...

For this reason, you should use the following procedure to upload under these conditions:

1. Press and release the button marked "RESET" on the board quickly twice. The LED marked "L" on the board should now be pulsing.

2. Select the port of the board from the menu in Arduino IDE. The port might have changed after the previous step, so make sure to verify that it is selected.

3. Upload your sketch as usual.

Keyboard

To use keyboard functionalities, we need to include the library at the top of our sketch. The Keyboard class contains several methods that are useful to emulate a keyboard.

Copy
1#include <Keyboard.h>
2
3Keyboard.method()

Keyboard Example

To emulate a keyboard, we can use the

press()

releaseAll()

Copy
1#include <Keyboard.h>
2
3void setup() {
4  Keyboard.begin();
5  delay(1000);
6}
7
8void loop() {
9  Keyboard.press('w');
10  delay(100);
11  Keyboard.releaseAll();
12  delay(1000); 
13}

To see more examples, please refer to links below:

• Keyboard and Mouse Control Tutorial
• Keyboard Reprogram Tutorial
• Keyboard Serial Tutorial
• Keyboard Logout Tutorial
• Keyboard Message Tutorial

Mouse

To use mouse functionalities, we need to include the library at the top of our sketch. The Mouse class contains several methods that are useful to emulate a mouse.

Copy
1#include <Mouse.h>
2
3Mouse.method();

Mouse Example

The following example moves both axis of mouse just slightly (10 points), back and forth.

Copy
1#include <Mouse.h>
2
3void setup() {
4  Mouse.begin();
5  delay(1000);
6}
7
8void loop() {
9  Mouse.move(10,10);
10  delay(1000);
11  Mouse.move(-10,-10);
12  delay(1000); 
13}

To see more examples, please refer to links below:

• Keyboard and Mouse Control Tutorial
• Button Mouse Control Tutorial
• Joystick Mouse Control Tutorial

Summary

In this tutorial, we have demonstrated some basic HID usage with the UNO R4 WiFi. To view the full API, please refer to the following APIs:

• Keyboard
• Mouse

In there, you will find a detailed reference along with some good examples to get you started with HID features.