У вашего броузера проблема в совместимости с HTML5
This is a "Hello World" test to drive a servo using an Arduino and Adafruit's PWM/Servo Driver.
Product page: Adafruit 16-Channel 12-bit PWM/Servo Driver - I2C interface - PCA9685: http://www.adafruit.com/products/815
Arduino sketch source: https://github.com/adafruit/Adafruit-PWM-Servo-Driver-Library/tree/master/examples/servo