This is a breakout module for Playstation2 analog joystick . There are 5 pins on board: VCC, GND, X, Y and Button. Connect the module with 5V power suppy with VCC and GND, you can read out the joystick status by X,Y and button pins. When using the 5V power supply, the default analog output for X,Y is 2.5V. With the direction of the arrow, the voltage up to 5V, and the opposite direction down to 0V.
JoyStick Breakout Module Sensor Shield For Robot Arduino UNO 2560 R3 STM32 A072