Module - PCA9685 - Servo motor driver PWM 16 Kanaals 12-bit I2C

Hardware

Met deze module kan men 16 servo’s aansturen via I2C met gekoppelde modules (max 62) tot max 992 servo’s!

Specificaties (eng):

It’s an i2c-controlled PWM driver with a built in clock. That means that, unlike the TLC5940 family, you do not need to continuously send it signal tying up your microcontroller, its completely free running!
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

I2C adres instellen

Board 0: Address = 0x40 Offset = binary 00000 (no jumpers required)
Board 1: Address = 0x41 Offset = binary 00001 (bridge A0 as in the photo above)
Board 2: Address = 0x42 Offset = binary 00010 (bridge A1)
Board 3: Address = 0x43 Offset = binary 00011 (bridge A0 & A1)
Board 4: Address = 0x44 Offset = binary 00100 (bridge A2)

Voorbeeld van meerder servo’s aangesloten:

Voorbeeld meerdere modules aangesloten:

Pinout

Arduino

Sluit de module aan volgens onderstaand overzicht:

Script

Onderstaand script maakt gebruik van de “Adafruit-PWM-Servo-Drive” bibliotheek.

#include <Wire.h>
#include <Adafruit_PWMServoDriver.h>

// called this way, it uses the default address 0x40
Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver();
// you can also call it with a different address you want
//Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver(0x41);
// you can also call it with a different address and I2C interface
//Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver(&Wire, 0x40);

// Depending on your servo make, the pulse width min and max may vary, you 
// want these to be as small/large as possible without hitting the hard stop
// for max range. You'll have to tweak them as necessary to match the servos you
// have!
#define SERVOMIN  150 // this is the 'minimum' pulse length count (out of 4096)
#define SERVOMAX  600 // this is the 'maximum' pulse length count (out of 4096)

// our servo # counter
uint8_t servonum = 0;

void setup() {
  Serial.begin(9600);
  Serial.println("8 channel Servo test!");

  pwm.begin();
  
  pwm.setPWMFreq(60);  // Analog servos run at ~60 Hz updates

  delay(10);
}

// you can use this function if you'd like to set the pulse length in seconds
// e.g. setServoPulse(0, 0.001) is a ~1 millisecond pulse width. its not precise!
void setServoPulse(uint8_t n, double pulse) {
  double pulselength;
  
  pulselength = 1000000;   // 1,000,000 us per second
  pulselength /= 60;   // 60 Hz
  Serial.print(pulselength); Serial.println(" us per period"); 
  pulselength /= 4096;  // 12 bits of resolution
  Serial.print(pulselength); Serial.println(" us per bit"); 
  pulse *= 1000000;  // convert to us
  pulse /= pulselength;
  Serial.println(pulse);
  pwm.setPWM(n, 0, pulse);
}

void loop() {
  // Drive each servo one at a time
  Serial.println(servonum);
  for (uint16_t pulselen = SERVOMIN; pulselen < SERVOMAX; pulselen++) {
    pwm.setPWM(servonum, 0, pulselen);
  }

  delay(500);
  for (uint16_t pulselen = SERVOMAX; pulselen > SERVOMIN; pulselen--) {
    pwm.setPWM(servonum, 0, pulselen);
  }

  delay(500);

  servonum ++;
  if (servonum > 7) servonum = 0;
}

#include <Wire.h>

#include <Adafruit_PWMServoDriver.h>

// called this way, it uses the default address 0x40

Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver();

// you can also call it with a different address you want

//Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver(0x41);

// you can also call it with a different address and I2C interface

//Adafruit_PWMServoDriver pwm = Adafruit_PWMServoDriver(&Wire, 0x40);

// Depending on your servo make, the pulse width min and max may vary, you

// want these to be as small/large as possible without hitting the hard stop

// for max range. You'll have to tweak them as necessary to match the servos you

// have!

#define SERVOMIN 150 // this is the 'minimum' pulse length count (out of 4096)

#define SERVOMAX 600 // this is the 'maximum' pulse length count (out of 4096)

// our servo # counter

uint8_t servonum = 0;

void setup() {

Serial.begin(9600);

Serial.println("8 channel Servo test!");

pwm.begin();

pwm.setPWMFreq(60); // Analog servos run at ~60 Hz updates

delay(10);

}

// you can use this function if you'd like to set the pulse length in seconds

// e.g. setServoPulse(0, 0.001) is a ~1 millisecond pulse width. its not precise!

void setServoPulse(uint8_t n, double pulse) {

double pulselength;

pulselength = 1000000; // 1,000,000 us per second

pulselength /= 60; // 60 Hz

Serial.print(pulselength); Serial.println(" us per period");

pulselength /= 4096; // 12 bits of resolution

Serial.print(pulselength); Serial.println(" us per bit");

pulse *= 1000000; // convert to us

pulse /= pulselength;

Serial.println(pulse);

pwm.setPWM(n, 0, pulse);

}

void loop() {

// Drive each servo one at a time

Serial.println(servonum);

for (uint16_t pulselen = SERVOMIN; pulselen < SERVOMAX; pulselen++) {

pwm.setPWM(servonum, 0, pulselen);

}

delay(500);

for (uint16_t pulselen = SERVOMAX; pulselen > SERVOMIN; pulselen--) {

pwm.setPWM(servonum, 0, pulselen);

}

delay(500);

servonum ++;

if (servonum > 7) servonum = 0;

}

Arduino Library

Installatie van Arduino IDE libraries: Arduino info

Informatie (ENG):

These drivers use I2C to communicate, 2 pins are required to interface.

Adafruit invests time and resources providing this open source code, please support Adafruit and open-source hardware by purchasing products from Adafruit!

Written by Limor Fried/Ladyada for Adafruit Industries. BSD license, check license.txt for more information.

All text above must be included in any redistribution

Compatibility

MCU	Tested Works	Not Tested	Notes
Atmega328 @ 16MHz	X
Atmega328 @ 12MHz	X
Atmega32u4 @ 16MHz	X
Atmega32u4 @ 8MHz	X
ESP8266	X
Atmega2560 @ 16MHz	X
ATSAM3X8E	X		Use SDA1/SCL1
ATSAM21D	X
ATtiny85 @ 16MHz	X
ATtiny85 @ 8MHz	X
Intel Curie @ 32MHz		X
STM32F2		X

ATmega328 @ 16MHz : Arduino UNO, Adafruit Pro Trinket 5V, Adafruit Metro 328, Adafruit Metro Mini
ATmega328 @ 12MHz : Adafruit Pro Trinket 3V
ATmega32u4 @ 16MHz : Arduino Leonardo, Arduino Micro, Arduino Yun, Teensy 2.0
ATmega32u4 @ 8MHz : Adafruit Flora, Bluefruit Micro
ESP8266 : Adafruit Huzzah
ATmega2560 @ 16MHz : Arduino Mega
ATSAM3X8E : Arduino Due
ATSAM21D : Arduino Zero, M0 Pro
ATtiny85 @ 16MHz : Adafruit Trinket 5V
ATtiny85 @ 8MHz : Adafruit Gemma, Arduino Gemma, Adafruit Trinket 3V

Download @ github.com

Adafruit-PWM-Servo-Driver-Library-master.7z 7,06 kb

Raspberry Pi

Sluit de module aan zoals aangegeven op onderstaand schema:

Ps. Altijd de pinout van je Raspberry Pi controleren, deze kan verschillen per versie.

Wat moet je doen?

1) I2C aanzetten op de Pi.
2) SMBUS module installeren voor Python:

Om de I²C bus in Python te gebruiken moet je een module installeren, genaamd SMBUS, dit kan via APT-GET met het commando: sudo apt-get install python-smbus

Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
  python-smbus
0 upgraded, 1 newly installed, 0 to remove and 79 not upgraded.
Need to get 11.9 kB of archives.
After this operation, 95.2 kB of additional disk space will be used.
Get:1 http://archive.raspberrypi.org/debian/ wheezy/main python-smbus armhf 3.1.1+svn-1 [11.9 kB]
Fetched 11.9 kB in 0s (131 kB/s)
Selecting previously unselected package python-smbus.
(Reading database ... 78301 files and directories currently installed.)
Unpacking python-smbus (from .../python-smbus_3.1.1+svn-1_armhf.deb) ...
Setting up python-smbus (3.1.1+svn-1) ...

Reading package lists... Done

Building dependency tree

Reading state information... Done

The following NEW packages will be installed:

python-smbus

0 upgraded, 1 newly installed, 0 to remove and 79 not upgraded.

Need to get 11.9 kB of archives.

After this operation, 95.2 kB of additional disk space will be used.

Get:1 http://archive.raspberrypi.org/debian/ wheezy/main python-smbus armhf 3.1.1+svn-1 [11.9 kB]

Fetched 11.9 kB in 0s (131 kB/s)

Selecting previously unselected package python-smbus.

(Reading database ... 78301 files and directories currently installed.)

Unpacking python-smbus (from .../python-smbus_3.1.1+svn-1_armhf.deb) ...

Setting up python-smbus (3.1.1+svn-1) ...

Je kan dan de module importeren in python door middel van: import smbus

Controleren van de aansluiting

Om de aansluiting van de module te controleren voor je het volgende commando uit: sudo i2cdetect -y 1, je ziet dan het (0x40) adres staan in de lijst: