Introduction: Mastering Servo Control With PCA9685 and Arduino

Our step-by-step guide on using the PCA9685 16-channel PWM/Servo Driver with Arduino! In this tutorial, we focus on how to control multiple servo motors efficiently. Let's dive in!

Supplies

Arduino Uno R3

8 * SG90 Servo Motors

PCA9685 16-Channel Module

External 5v-Adaptor

Jumper Wires

Step 1: Understanding the PCA9685 Module

The PCA9685 module is an excellent tool for precise control of multiple PWM outputs, commonly used in applications like robotics, automation, and lighting. It offers 16 channels for controlling servos, LEDs, and other devices.

Step 2: Servo Interfacing With Arduino

Servo motors require PWM pulses to operate. They have three wires: VCC, GND, and PWM. Connect them to your Arduino as follows:

  • VCC to 5v
  • GND to Ground
  • PWM to any digital PWM pin


Step 3: Using the Servo.h Library

Upload the Sweep Sketch from the Servo.h library in the Arduino IDE to rotate the servo from 0 to 180 and vice versa.

Step 4: Multi-Servos Interfacing

Arduino has limited PWM output pins, so controlling multiple servos can be challenging. The PCA9685 module solves this problem by offering 16 free-running PWM outputs.


Step 5: Connecting the PCA9685 Module

Connect the PCA9685 module to your Arduino:

  1. VCC to 5v
  2. GND to Ground
  3. SDA to A4
  4. SCL to A5


Step 6: Programming the PCA9685 With Arduino

Use the Adafruit_PWMServoDriver.h library to control the PCA9685 module. Set the PWM frequency to 60Hz and define the minimum and maximum pulse lengths.

Step 7: Writing the Code

Write the code (github link) to rotate the servos synchronously using the setPWM() function. Sweep the servos from 0 to 180 angle and back.

Step 8: Testing and Troubleshooting

Check all connections before powering up. Monitor angle and pulse data on the serial display. Use an external adapter for power if necessary.