A lightweight, reliable servo testing and calibration toolkit for robotics, animatronics, and embedded systems.
This repository contains standalone servo tester programs written in both:
- Arduino (
.ino) for direct hardware testing - Python (
.py) for PC / GUI / serial-based control
Designed to help you verify hardware, debug wiring issues, and calibrate servos safely before integrating them into larger systems.
Before complex control logic (animations, expressions, AI, etc.), you must ensure:
- Every servo works
- Every channel outputs PWM
- PCA9685 drivers are configured correctly
- Pulse ranges are safe
This repository solves that first-principles problem.
- ✅ Test any servo on any PCA9685 channel
- 🔄 Center all servos instantly
- 🎚️ Angle-based & pulse-based control
- 🔍 Detect dead channels or wiring faults
- 🖥️ Python-based serial control (GUI-friendly)
- ⚙️ Supports PCA9685 @ 50 Hz
- 🧪 Ideal for debugging before final integration
- Control by:
- Channel number
- Angle
- Pulse width
- Includes safety limits
- Ideal for servo calibration
- Sweeps all 16 PCA9685 channels
- Detects dead or miswired outputs
- Useful for diagnosing:
- Broken traces
- Unsoldered V+ jumper
- I²C issues
- Serial-based servo control
- Sends commands to Arduino
- Great for scripting tests
- Channel-specific testing
- Pulse-width tuning
- Debugging PWM output accuracy
- GUI-ready backend
- Designed for PyQt / Tkinter integration
- Suitable for large servo arrays
- Microcontroller (anyone of these would work)
- Arduino UNO / Nano / Mega
- Seeed XIAO SAMD21
- ESP32 (logic-level compatible)
- Raspberry pi Pico
- PCA9685 16-channel servo driver
- Servo motors (SG90 / MG90 / metal gear recommended)
- External 5V-10Amps power supply for servo motors (do not power servos from MCU)
- Common ground between MCU & PCA9685
- PCA9685 I²C address:
0x40 - PWM Frequency: 50 Hz
- Pulse range:
- 500–2500 µs (standard servos)
- or PCA ticks (150–600)