DIY Joystick Game Controller using Arduino Leonardo and Joystick Module
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Zerk Zone - Arduino Leonardo Custom Joystick
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Create a Joystick Using the Arduino Joystick Library 2.0 : 12 Steps (with Pictures) - Instructables
I made a gaming control panel using an Arduino Leonardo to play simulators. Currently using it for DCS World, but it should work in most games just like any joystick / gamepad.
Analoge joystick on Arduino Leonardo - Project Guidance - Arduino Forum
Arduino Prebuilds Sensors, Joystick Into New Esplora Microcontroller | WIRED