How to Use KY-020: Examples, Pinouts, and Specs

The KY-020 is a simple analog joystick module designed for two-dimensional control. Manufactured by Arduino, this module features two potentiometers that detect the position of the joystick along the X and Y axes. The output is provided as variable voltage signals, which can be easily read by microcontrollers such as the Arduino UNO. Additionally, the module includes a push-button switch that activates when the joystick is pressed down.

• Robotics: Control of robotic arms, vehicles, or drones.
• Gaming: Used as an input device for custom game controllers.
• User Interfaces: Navigation in graphical user interfaces.
• Educational Projects: Ideal for learning about analog input and microcontroller interfacing.

The KY-020 joystick module has the following key specifications:

The KY-020 module has 5 pins, as described in the table below:

1. Power the Module: Connect the +5V pin to the 5V output of your microcontroller and the GND pin to ground.
2. Read the X and Y Axes: Connect the VRx and VRy pins to analog input pins on your microcontroller to read the joystick's position.
3. Monitor the Push-Button: Connect the SW pin to a digital input pin to detect when the joystick is pressed.
4. Pull-Up Resistor for SW: If the microcontroller does not have an internal pull-up resistor, connect an external pull-up resistor (e.g., 10 kΩ) between the SW pin and +5V.

• Debouncing the Push-Button: Use software or hardware debouncing to ensure reliable detection of the button press.
• Voltage Compatibility: Ensure the module's operating voltage matches your microcontroller's input voltage range.
• Calibration: The joystick's analog outputs may vary slightly due to manufacturing tolerances. Calibrate the readings in your software for precise control.

Below is an example Arduino sketch to read the joystick's X and Y positions and detect button presses:

// Define pin connections
const int VRxPin = A0; // X-axis analog output connected to A0
const int VRyPin = A1; // Y-axis analog output connected to A1
const int SWPin = 2;   // Push-button digital output connected to D2

void setup() {
  // Initialize serial communication for debugging
  Serial.begin(9600);

  // Configure the SW pin as input with an internal pull-up resistor
  pinMode(SWPin, INPUT_PULLUP);
}

void loop() {
  // Read the X and Y axis values (0 to 1023)
  int xValue = analogRead(VRxPin);
  int yValue = analogRead(VRyPin);

  // Read the state of the push-button (LOW when pressed)
  bool buttonPressed = !digitalRead(SWPin);

  // Print the joystick values to the Serial Monitor
  Serial.print("X: ");
  Serial.print(xValue);
  Serial.print(" | Y: ");
  Serial.print(yValue);
  Serial.print(" | Button: ");
  Serial.println(buttonPressed ? "Pressed" : "Released");

  // Add a small delay for stability
  delay(100);
}

1. No Output from the Module

   • Cause: Incorrect wiring or insufficient power supply.
   • Solution: Double-check the connections and ensure the module is powered with 3.3V to 5V.

2. Inconsistent Analog Readings

   • Cause: Electrical noise or poor connections.
   • Solution: Use shorter wires and ensure secure connections. Add capacitors (e.g., 0.1 µF) near the power pins to filter noise.

3. Push-Button Not Detected

   • Cause: Missing pull-up resistor.
   • Solution: Enable the internal pull-up resistor in your microcontroller or add an external pull-up resistor.

4. Joystick Center Position Not Zero

   • Cause: Manufacturing tolerances.
   • Solution: Calibrate the joystick in your software to account for the offset.

Q1: Can the KY-020 be used with 3.3V microcontrollers like the ESP32?
A1: Yes, the KY-020 operates at 3.3V to 5V, making it compatible with 3.3V microcontrollers.

Q2: How do I increase the precision of the joystick readings?
A2: Use the microcontroller's ADC with higher resolution (e.g., 12-bit ADC) if available, and implement software filtering.

Q3: Can I use the KY-020 for 3D control?
A3: No, the KY-020 only supports two-dimensional control (X and Y axes). For 3D control, consider a joystick with an additional Z-axis.