ESP32_OSC_IMU/lib/M5Stack/examples/Modules/SERVO2_PCA9685/Adafruit_PWMServoDriver.h

/*!
 *  @file Adafruit_PWMServoDriver.h
 *
 *  This is a library for our Adafruit 16-channel PWM & Servo driver.
 *
 *  Designed specifically to work with the Adafruit 16-channel PWM & Servo
 * driver.
 *
 *  Pick one up today in the adafruit shop!
 *  ------> https://www.adafruit.com/product/815
 *
 *  These driver use I2C to communicate, 2 pins are required to interface.
 *  For Arduino UNOs, thats SCL -> Analog 5, SDA -> Analog 4.
 *
 *  Adafruit invests time and resources providing this open source code,
 *  please support Adafruit andopen-source hardware by purchasing products
 *  from Adafruit!
 *
 *  Limor Fried/Ladyada (Adafruit Industries).
 *
 *  BSD license, all text above must be included in any redistribution
 */
#ifndef _ADAFRUIT_PWMServoDriver_H
#define _ADAFRUIT_PWMServoDriver_H

#include <Arduino.h>
#include <Wire.h>

// REGISTER ADDRESSES
#define PCA9685_MODE1 0x00      /**< Mode Register 1 */
#define PCA9685_MODE2 0x01      /**< Mode Register 2 */
#define PCA9685_SUBADR1 0x02    /**< I2C-bus subaddress 1 */
#define PCA9685_SUBADR2 0x03    /**< I2C-bus subaddress 2 */
#define PCA9685_SUBADR3 0x04    /**< I2C-bus subaddress 3 */
#define PCA9685_ALLCALLADR 0x05 /**< LED All Call I2C-bus address */
#define PCA9685_LED0_ON_L 0x06  /**< LED0 on tick, low byte*/
#define PCA9685_LED0_ON_H 0x07  /**< LED0 on tick, high byte*/
#define PCA9685_LED0_OFF_L 0x08 /**< LED0 off tick, low byte */
#define PCA9685_LED0_OFF_H 0x09 /**< LED0 off tick, high byte */
// etc all 16:  LED15_OFF_H 0x45
#define PCA9685_ALLLED_ON_L 0xFA  /**< load all the LEDn_ON registers, low */
#define PCA9685_ALLLED_ON_H 0xFB  /**< load all the LEDn_ON registers, high */
#define PCA9685_ALLLED_OFF_L 0xFC /**< load all the LEDn_OFF registers, low */
#define PCA9685_ALLLED_OFF_H 0xFD /**< load all the LEDn_OFF registers,high */
#define PCA9685_PRESCALE 0xFE     /**< Prescaler for PWM output frequency */
#define PCA9685_TESTMODE 0xFF     /**< defines the test mode to be entered */

// MODE1 bits
#define MODE1_ALLCAL 0x01  /**< respond to LED All Call I2C-bus address */
#define MODE1_SUB3 0x02    /**< respond to I2C-bus subaddress 3 */
#define MODE1_SUB2 0x04    /**< respond to I2C-bus subaddress 2 */
#define MODE1_SUB1 0x08    /**< respond to I2C-bus subaddress 1 */
#define MODE1_SLEEP 0x10   /**< Low power mode. Oscillator off */
#define MODE1_AI 0x20      /**< Auto-Increment enabled */
#define MODE1_EXTCLK 0x40  /**< Use EXTCLK pin clock */
#define MODE1_RESTART 0x80 /**< Restart enabled */
// MODE2 bits
#define MODE2_OUTNE_0 0x01 /**< Active LOW output enable input */
#define MODE2_OUTNE_1                                                          \
  0x02 /**< Active LOW output enable input - high impedience */
#define MODE2_OUTDRV 0x04 /**< totem pole structure vs open-drain */
#define MODE2_OCH 0x08    /**< Outputs change on ACK vs STOP */
#define MODE2_INVRT 0x10  /**< Output logic state inverted */

#define PCA9685_I2C_ADDRESS 0x40      /**< Default PCA9685 I2C Slave Address */
#define FREQUENCY_OSCILLATOR 25000000 /**< Int. osc. frequency in datasheet */

#define PCA9685_PRESCALE_MIN 3   /**< minimum prescale value */
#define PCA9685_PRESCALE_MAX 255 /**< maximum prescale value */

/*!
 *  @brief  Class that stores state and functions for interacting with PCA9685
 * PWM chip
 */
class Adafruit_PWMServoDriver {
public:
  Adafruit_PWMServoDriver();
  Adafruit_PWMServoDriver(const uint8_t addr);
  Adafruit_PWMServoDriver(const uint8_t addr, TwoWire &i2c);
  void begin(uint8_t prescale = 0);
  void reset();
  void sleep();
  void wakeup();
  void setExtClk(uint8_t prescale);
  void setPWMFreq(float freq);
  void setOutputMode(bool totempole);
  uint8_t getPWM(uint8_t num);
  void setPWM(uint8_t num, uint16_t on, uint16_t off);
  void setPin(uint8_t num, uint16_t val, bool invert = false);
  uint8_t readPrescale(void);
  void writeMicroseconds(uint8_t num, uint16_t Microseconds);

  void setOscillatorFrequency(uint32_t freq);
  uint32_t getOscillatorFrequency(void);

private:
  uint8_t _i2caddr;
  TwoWire *_i2c;

  uint32_t _oscillator_freq;
  uint8_t read8(uint8_t addr);
  void write8(uint8_t addr, uint8_t d);
};

#endif