/arduino-adafruit-pwm-servo

Arduino Adafruit PWM servo library

Primary LanguageC++OtherNOASSERTION

Arduino Adafruit - 16-Channel 12-bit PWM/Servo Driver - I2C interface - PCA9685 library for Mongoose OS

Tested and works on esp8266/esp32

Description

16-Channel 12-bit PWM/Servo Driver – I2C interface – PCA9685 Module lets you add more IOs to your microcontroller boards. The Module has chainable I2C interface meaning for even more IOs more boards can be daisy chained. Its and excellent product for Robots that require lots of Servo motors to control using single microcontroller.See product page link for more information about the hardware.

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Features

  • It is 5V compliant, which means you can control it from a 3.3V microcontroller and still safely drive up to 6V outputs (this is good for when you want to control white or blue LEDs with 3.4+ forward voltages)
  • 6 address select pins so you can wire up to 62 of these on a single i2c bus, a total of 992 outputs – that’s a lot of servos or LEDs
  • Adjustable frequency PWM up to about 1.6 KHz
  • 12-bit resolution for each output – for servos, that means about 4us resolution at 60Hz update rate
  • Configurable push-pull or open-drain output
  • Output enable pin to quickly disable all the outputs
  • Reverse polarity protection on the terminal block input
  • Power-good LED
  • 3 pin connectors in groups of 4 so you can plug in 16 servos at once
  • A big capacitor on the V+ line
  • 220 ohm series resistors on all the output lines to protect them, and to make driving LEDs trivial
  • IO expander chip: PCA9685PW
  • Operating Voltage: 2.3V – 5.5V
  • Solder jumpers for the 6 address select pins
  • I2C 7-bit address Range: between 0x40-0x7F, selectable with jumpers

Usage

mos.yml, add:

config_schema:
 - ["i2c.enable", true]
libs:
 - origin: https://github.com/mongoose-os-libs/arduino-adafruit-pwm-servo

init.js, add:

load('api_pwm_servo.js');

main.c, add:

#include "mgos_arduino_PWMServoDriver.h"

Slave address

  • Board 0: Address = 0x40 Offset = binary 00000 (no jumpers required)
  • Board 1: Address = 0x41 Offset = binary 00001 (bridge A0 )
  • Board 2: Address = 0x42 Offset = binary 00010 (bridge A1)
  • Board 3: Address = 0x43 Offset = binary 00011 (bridge A0 & A1)
  • ...