ServoEasing.h

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/*
 * ServoEasing.h
 *
 *  Copyright (C) 2019-2025  Armin Joachimsmeyer
 *  armin.joachimsmeyer@gmail.com
 *
 *  This file is part of ServoEasing https://github.com/ArminJo/ServoEasing.
 *
 *  ServoEasing is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *  See the GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program. If not, see <http://www.gnu.org/licenses/gpl.html>.
 */
 
#ifndef _SERVO_EASING_H
#define _SERVO_EASING_H
 
#define VERSION_SERVO_EASING "3.6.0"
#define VERSION_SERVO_EASING_MAJOR 3
#define VERSION_SERVO_EASING_MINOR 6
#define VERSION_SERVO_EASING_PATCH 0
// The change log is at the bottom of the file
 
#if defined(USE_LEIGHTWEIGHT_SERVO_LIB)
#define USE_LIGHTWEIGHT_SERVO_LIBRARY // for backwards compatibility
#endif
 
/*
 * Macro to convert 3 version parts into an integer
 * To be used in preprocessor comparisons, such as #if VERSION_SERVO_EASING_HEX >= VERSION_HEX_VALUE(3, 0, 0)
 */
#define VERSION_HEX_VALUE(major, minor, patch) ((major << 16) | (minor << 8) | (patch))
#define VERSION_SERVO_EASING_HEX  VERSION_HEX_VALUE(VERSION_SERVO_EASING_MAJOR, VERSION_SERVO_EASING_MINOR, VERSION_SERVO_EASING_PATCH)
 
#if !defined(MILLIS_IN_ONE_SECOND)
#define MILLIS_IN_ONE_SECOND 1000L
#endif
 
// The eclipse formatter has problems with // comments in undefined code blocks
// !!! Must be without trailing comment and closed by @formatter:on
// @formatter:off
#define START_EASE_TO_SPEED 5 // If not specified use 5 degree per second. It is chosen so low in order to signal that it was forgotten to specify by program.
 
/*
 * USE_PCA9685_SERVO_EXPANDER is for use with e.g. the Adafruit PCA9685 16-Channel Servo Driver board.
 * It has a resolution of 4096 per 20 ms => 4.88 us per step/unit.
 * One PCA9685 has 16 outputs. You must modify MAX_EASING_SERVOS below, if you have more than one PCA9685 attached!
 * All internal values *MicrosecondsOrUnits now contains no more microseconds but PCA9685 units!!!
 */
//#define USE_PCA9685_SERVO_EXPANDER
/*
 * Use of PCA9685 normally disables use of regular servo library to save programming space and RAM.
 * You can force additional using of regular servo library by defining USE_SERVO_LIB.
 * Therefore it is only required if USE_PCA9685_SERVO_EXPANDER is defined.
 */
//#define USE_SERVO_LIB
 
/*
 * If you have a different servo implementation, e.g. this M5Stack Servo expander https://shop.m5stack.com/products/8-channel-servo-driver-unit-stm32f030
 * you can provide your own servo library by activating USE_USER_PROVIDED_SERVO_LIB
 * You must also include the .h file of your library e.g. `#include "DummyServo.h"`.
 * The library must define a class "Servo" and implement: attach(pin, min, max), detach() and writeMicroseconds(value).
 */
//#define USE_USER_PROVIDED_SERVO_LIB
//#include <DummyServo.h>
 
/*
 * If you have only one or two servos at pin 9 and/or 10 and an ATmega328, then you can save program memory by defining symbol `USE_LIGHTWEIGHT_SERVO_LIBRARY`.
 * This saves 742 bytes program memory and 42 bytes RAM.
 * Using Lightweight Servo library (or PCA9685 servo expander) makes the servo pulse generating immune
 * to other libraries blocking interrupts for a longer time like SoftwareSerial, Adafruit_NeoPixel and DmxSimple.
 * If not using the Arduino IDE take care that Arduino Servo library sources are not compiled / included in the project.
 * Use of Lightweight Servo library disables use of regular servo library.
 */
//#define USE_LIGHTWEIGHT_SERVO_LIBRARY
 
#if defined(USE_LIGHTWEIGHT_SERVO_LIBRARY) && !(defined(__AVR_ATmega328P__) || defined(__AVR_ATmega328__) || defined (__AVR_ATmega328PB__) || defined(__AVR_ATmega2560__))
#error USE_LIGHTWEIGHT_SERVO_LIBRARY can only be activated for the Atmega328 or ATmega2560 CPU
#endif
 
/*
 * If defined, the void handleServoTimerInterrupt() function must be provided by the user program.
 * This enables the reuse of the Servo timer interrupt e.g. for synchronizing with NeoPixel updates,
 * which otherwise leads to servo twitching. See QuadrupedNeoPixel.cpp of QuadrupedControl example.
 * This interrupt routine is called in an ISR context and (at least on Uno, Nano etc.) 100 microseconds
 * before a new servo period starts to leave the first servo signals undisturbed.
 * See also setTimer1InterruptMarginMicros()
 */
//#define ENABLE_EXTERNAL_SERVO_TIMER_HANDLER
#if defined(ENABLE_EXTERNAL_SERVO_TIMER_HANDLER)
extern void handleServoTimerInterrupt();
#endif
 
#if !( defined(__AVR__) || defined(ESP8266) || defined(ESP32) || defined(STM32F1xx) || defined(__STM32F1__) || defined(__SAM3X8E__) || defined(ARDUINO_ARCH_SAMD) || defined(ARDUINO_ARCH_APOLLO3) || defined(ARDUINO_ARCH_MBED) || defined(ARDUINO_ARCH_RP2040) || defined(TEENSYDUINO))
#warning No periodic timer support existent (or known) for this platform. Only blocking functions and simple example will run!
#endif
 
/*
 * Include of the appropriate Servo.h file
 */
#if !defined(USE_USER_PROVIDED_SERVO_LIB) && (!defined(USE_PCA9685_SERVO_EXPANDER) || defined(USE_SERVO_LIB))
#  if defined(ESP32)
// This does not work in Arduino IDE for step "Generating function prototypes..."
//#    if ! __has_include("ESP32Servo.h")
//#error This ServoEasing library requires the "ESP32Servo" library for running on an ESP32. Please install it via the Arduino library manager.
//#    endif
#include <ESP32Servo.h>
 
#  elif defined(MEGATINYCORE)
#include <Servo_megaTinyCore.h>
 
#  elif defined(MEGACOREX)
#    if __has_include("ServoMegaCoreX.h")
#include <ServoMegaCoreX.h> // since Version 1.1.1 of MEGACOREX
#    else
#include <Servo.h>
#    endif
 
#  else // defined(ESP32)
#    if defined(USE_LIGHTWEIGHT_SERVO_LIBRARY)
#include "LightweightServo.h"
#      if !defined(MAX_EASING_SERVOS)
#        if defined(__AVR_ATmega2560__)
#define MAX_EASING_SERVOS 3 // default value for Mega.
#        else
#define MAX_EASING_SERVOS 2 // default value for Uno etc.
#        endif
#      endif
#    else
#include <Servo.h>
#    endif // !defined(USE_LIGHTWEIGHT_SERVO_LIBRARY)
#  endif // defined(ESP32)
#endif // defined(USE_SERVO_LIB)
 
#if defined(ARDUINO_ARCH_MBED) // Arduino Nano 33 BLE
#include "mbed.h"
#endif
 
#if defined(USE_PCA9685_SERVO_EXPANDER)
#  if !defined(MAX_EASING_SERVOS)
#define MAX_EASING_SERVOS 16 // One PCA9685 has 16 outputs. You must MODIFY this, if you have more than one PCA9685 attached!
#  endif // defined(USE_PCA9685_SERVO_EXPANDER)
   #include <Wire.h>
// PCA9685 works with up to 1 MHz I2C frequency according to the datasheet
#  if !defined(I2C_CLOCK_FREQUENCY)
#    if defined(ESP32)
// The ESP32 I2C interferes with the Ticker / Timer library used.
// Even with 100 kHz clock we have some dropouts / NAK's because of sending address again instead of first data.
# define I2C_CLOCK_FREQUENCY 100000 // 200000 does not work for my ESP32 module together with the timer even with external pullups :-(
#    elif defined(ESP8266)
#define I2C_CLOCK_FREQUENCY 400000 // 400000 is the maximum for 80 MHz clocked ESP8266 (I measured real 330000 Hz for this setting)
#    else
#define I2C_CLOCK_FREQUENCY 800000 // 1 MHz from datasheet does not work for my Arduino Nano, maybe because of parasitic breadboard capacities
#    endif
#  endif
#endif // defined(USE_PCA9685_SERVO_EXPANDER)
 
/*****************************************************************************************
 * Important definition of MAX_EASING_SERVOS !!!
 * If this value is smaller than the amount of servos declared,
 * attach() will return error and other library functions will not work as expected.
 * Of course all *AllServos*() functions and isOneServoMoving() can't work correctly!
 * Saves 4 byte RAM per servo.
 ****************************************************************************************/
#if !defined(MAX_EASING_SERVOS)
#  if defined(MAX_SERVOS) // defined in Sevos.h
#define MAX_EASING_SERVOS MAX_SERVOS // =12 use default value from Servo.h for Uno etc.
#  else
#define MAX_EASING_SERVOS 12 // just take default value from Servo.h for Uno etc.
#  endif
#endif // !defined(MAX_EASING_SERVOS)
 
#if !defined(DEFAULT_PULSE_WIDTH)
#define DEFAULT_PULSE_WIDTH 1500     // default pulse width when servo is attached (from Servo.h)
#endif
#if !defined(SERVO_REFRESH_INTERVAL) && defined(REFRESH_INTERVAL)
#define SERVO_REFRESH_INTERVAL_MICROS REFRESH_INTERVAL   // // minimum time to refresh servos in microseconds (from Servo.h)
#endif
#if !defined(SERVO_REFRESH_INTERVAL) && defined(REFRESH_USEC)
#define SERVO_REFRESH_INTERVAL_MICROS REFRESH_USEC   // // minimum time to refresh servos in microseconds (from ESP32Servo.h)
#endif
#if !defined(SERVO_REFRESH_INTERVAL_MICROS)
#define SERVO_REFRESH_INTERVAL_MICROS 20000   // // minimum time to refresh servos in microseconds (from Servo.h)
#endif
#if !defined(INVALID_SERVO)
#define INVALID_SERVO    255     // flag indicating an invalid servo index (from Servo.h)
#endif
#define SERVO_REFRESH_INTERVAL_MILLIS (SERVO_REFRESH_INTERVAL_MICROS/1000)  // 20 - used for delay()
#define SERVO_REFRESH_FREQUENCY (MILLIS_IN_ONE_SECOND/SERVO_REFRESH_INTERVAL_MILLIS) // 50
 
/*
 * Define `DISABLE_COMPLEX_FUNCTIONS` if space (1850 bytes) matters.
 * It disables the SINE, CIRCULAR, BACK, ELASTIC, BOUNCE and PRECISION easings.
 * The saving comes mainly from avoiding the sin() cos() sqrt() and pow() library functions in this code.
 * If you need only a single complex easing function and want to save space,
 * you can specify it any time as a user function. See EaseQuadraticInQuarticOut() function in AsymmetricEasing example line 206.
 */
#if !defined(DISABLE_COMPLEX_FUNCTIONS)
//#define DISABLE_COMPLEX_FUNCTIONS
#endif
 
/*
 * If you need only the linear movement you may define `PROVIDE_ONLY_LINEAR_MOVEMENT`. This saves additional 1540 bytes program memory.
 */
#if !defined(PROVIDE_ONLY_LINEAR_MOVEMENT)
//#define PROVIDE_ONLY_LINEAR_MOVEMENT
#endif
 
/*
 * If you do not require passing microsecond values as parameter instead of degree values. This saves 128 bytes program memory.
 */
//#define DISABLE_MICROS_AS_DEGREE_PARAMETER
 
#if !defined(THRESHOLD_VALUE_FOR_INTERPRETING_VALUE_AS_MICROSECONDS)
#define THRESHOLD_VALUE_FOR_INTERPRETING_VALUE_AS_MICROSECONDS  360  // treat values less than 360 as angles in degrees, others are handled as microseconds
#endif
 
#if !defined(va_arg)
// workaround for STM32
#include <stdarg.h>
#endif
 
// @formatter:on
/*
 * The next values are smaller and greater than the values used by the Arduino Servo library to be more versatile
 * They are used as parameter for the Arduino Servo attach() function, to avoid that the underlying Arduino writeMicroseconds()
 * clips its parameter value to 544 us (MIN_PULSE_WIDTH) and 2400 us (MAX_PULSE_WIDTH)
 * We do not use the Arduino write() function, which interprets this values as values for 0 and 180 degrees (and clips at 0 and 180 degrees).
 */
#if !defined(MINIMUM_PULSE_WIDTH)
#define MINIMUM_PULSE_WIDTH   400 // The shortest pulse which can be sent to a servo by this library. Checked by underlying Arduino writeMicroseconds().
#endif
#if !defined(MAXIMUM_PULSE_WIDTH)
#define MAXIMUM_PULSE_WIDTH  3500 // the longest pulse which can be sent sent to a servo by this library. Checked by underlying Arduino writeMicroseconds().
#endif
 
// Approximately 10 microseconds per degree
#define DEFAULT_MICROSECONDS_FOR_0_DEGREE     544
#define DEFAULT_MICROSECONDS_FOR_45_DEGREE   (544 + ((2400 - 544) / 4)) // 1008
#define DEFAULT_MICROSECONDS_FOR_90_DEGREE   (544 + ((2400 - 544) / 2)) // 1472
#define DEFAULT_MICROSECONDS_FOR_135_DEGREE (2400 - ((2400 - 544) / 4)) // 1936
#define DEFAULT_MICROSECONDS_FOR_180_DEGREE  2400
 
// Approximately 2 units per degree
#define DEFAULT_PCA9685_UNITS_FOR_0_DEGREE    111 // 111.411 = 544 us
#define DEFAULT_PCA9685_UNITS_FOR_45_DEGREE  (111 + ((491 - 111) / 4)) // 206
#define DEFAULT_PCA9685_UNITS_FOR_90_DEGREE  (111 + ((491 - 111) / 2)) // 301 = 1472 us
#define DEFAULT_PCA9685_UNITS_FOR_135_DEGREE (491 - ((491 - 111) / 4)) // 369
#define DEFAULT_PCA9685_UNITS_FOR_180_DEGREE  491 // 491.52 = 2400 us
 
/*
 * Definitions for continuous rotating servo - Values are taken from the Parallax Continuous Rotation Servo manual
 * and rely on a stop value of exactly 1500 microseconds.
 * If the stop value of your servo is NOT exactly 1500 microseconds, you must change the value of MICROSECONDS_FOR_ROTATING_SERVO_STOP.
 * My modified MG90 servo has 1630 and 1400 as max.
 *
 * Use attach(PIN, MICROSECONDS_FOR_ROTATING_SERVO_CLOCKWISE_MAX, MICROSECONDS_FOR_ROTATING_SERVO_COUNTER_CLOCKWISE_MAX, 100, -100);
 * Use write(100) for maximum clockwise and write(-100) for maximum counter clockwise rotation.
 */
#if !defined(MICROSECONDS_FOR_ROTATING_SERVO_STOP)
#define MICROSECONDS_FOR_ROTATING_SERVO_STOP 1500 // Change this value to your servos real stop value
#endif
/*
 * Definitions here are only for convenience. You may freely modify them.
 */
#define MICROSECONDS_FOR_ROTATING_SERVO_CLOCKWISE_MAX (MICROSECONDS_FOR_ROTATING_SERVO_STOP - 200)
#define MICROSECONDS_FOR_ROTATING_SERVO_CLOCKWISE_HALF (MICROSECONDS_FOR_ROTATING_SERVO_STOP - 100)
#define MICROSECONDS_FOR_ROTATING_SERVO_CLOCKWISE_QUARTER (MICROSECONDS_FOR_ROTATING_SERVO_STOP - 50)
#define MICROSECONDS_FOR_ROTATING_SERVO_COUNTER_CLOCKWISE_MAX (MICROSECONDS_FOR_ROTATING_SERVO_STOP + 200)
#define MICROSECONDS_FOR_ROTATING_SERVO_COUNTER_CLOCKWISE_HALF (MICROSECONDS_FOR_ROTATING_SERVO_STOP + 100)
#define MICROSECONDS_FOR_ROTATING_SERVO_COUNTER_CLOCKWISE_QUARTER (MICROSECONDS_FOR_ROTATING_SERVO_STOP + 50)
 
#if (!(defined(ENABLE_EASE_QUADRATIC) || defined(ENABLE_EASE_CUBIC) || defined(ENABLE_EASE_QUARTIC) \
|| defined(ENABLE_EASE_SINE) || defined(ENABLE_EASE_CIRCULAR) || defined(ENABLE_EASE_BACK) \
|| defined(ENABLE_EASE_USER) \
|| defined(ENABLE_EASE_ELASTIC) || defined(ENABLE_EASE_BOUNCE)|| defined(ENABLE_EASE_PRECISION) \
))
#define ENABLE_EASE_QUADRATIC
#define ENABLE_EASE_CUBIC
#define ENABLE_EASE_QUARTIC
#define ENABLE_EASE_USER
#  if !defined(DISABLE_COMPLEX_FUNCTIONS)
#define ENABLE_EASE_SINE
#define ENABLE_EASE_CIRCULAR
#define ENABLE_EASE_BACK
#define ENABLE_EASE_ELASTIC
#define ENABLE_EASE_BOUNCE
#define ENABLE_EASE_PRECISION
#  endif
#endif
 
/*
 * The different easing functions:
 *
 * In order to reuse the IN functions for OUT and IN_OUT functions, the following call and result conversions are used internally.
 * FactorOfMovementCompletion is multiplied with delta microseconds and added to StartPosition to get the current position.
 *
 * 1. Using IN function direct: Call with PercentageOfCompletion/100 | 0.0 to 1.0. FactorOfMovementCompletion is returnValue (from 0.0 to 1.0)
 * 2. Using IN function to generate OUT function: Call with (1 - PercentageOfCompletion/100) | 1.0 to 0.0. FactorOfMovementCompletion = (1 - returnValue)
 * 3. Using IN function to generate IN_OUT function:
 *      In the first half, call with (2 * PercentageOfCompletion/100) | 0.0 to 1.0. FactorOfMovementCompletion = (0.5 * returnValue)
 *      In the second half, call with (2 - (2 * PercentageOfCompletion/100)) | 1.0 to 0.0. FactorOfMovementCompletion = ( 1- (0.5 * returnValue))
 * 4. Using IN function to generate bouncing_OUT_IN / mirrored_OUT function, which return to start point (like the upper half of a sine):
 *      In the first half, call with (1 - (2 * PercentageOfCompletion/100)) | 1.0 to 0.0. FactorOfMovementCompletion = (1 - returnValue) -> call OUT 2 times faster.
 *      In the second half, call with ((2 * PercentageOfCompletion/100) - 1) | 0.0 to 1.0. FactorOfMovementCompletion = (1- returnValue) -> call OUT 2 times faster and backwards.
 *
 */
// Offset to decide if the user function returns degrees instead of 0.0 to 1.0.
#define EASE_FUNCTION_DEGREE_INDICATOR_OFFSET       200 // Returns 20 for -180 degree, 110 for -90 degree, 200 for 0 degree and 380 for 180 degree.
#define EASE_FUNCTION_DEGREE_THRESHOLD              (EASE_FUNCTION_DEGREE_INDICATOR_OFFSET - 180) // allows -180 degree.
#define EASE_FUNCTION_MICROSECONDS_INDICATOR_OFFSET (EASE_FUNCTION_DEGREE_INDICATOR_OFFSET + 200) // Offset to decide if the user function returns microseconds instead of 0.0 to 1.0. => returns 256 for 0 degree.
 
/*
 * Values for provided EaseTypes
 * The call style is coded in the upper 2 bits
 */
#define CALL_STYLE_DIRECT       0x00 // == IN
#define CALL_STYLE_IN           0x00
#define CALL_STYLE_OUT          0x40
#define CALL_STYLE_IN_OUT       0x80
#define CALL_STYLE_BOUNCING_OUT_IN  0xC0 // Bouncing has double movement, so double time (half speed) is taken for this modes
 
#define CALL_STYLE_MASK         0xC0
#define EASE_TYPE_MASK          0x0F
 
#define EASE_LINEAR             0x00 // No bouncing available
 
#if defined(ENABLE_EASE_QUADRATIC)
#define EASE_QUADRATIC_IN       0x01
#define EASE_QUADRATIC_OUT      0x41
#define EASE_QUADRATIC_IN_OUT   0x81
#define EASE_QUADRATIC_BOUNCING 0xC1
#endif
 
#if defined(ENABLE_EASE_CUBIC)
#define EASE_CUBIC_IN           0x02
#define EASE_CUBIC_OUT          0x42
#define EASE_CUBIC_IN_OUT       0x82
#define EASE_CUBIC_BOUNCING     0xC2
#endif
 
#if defined(ENABLE_EASE_QUARTIC)
#define EASE_QUARTIC_IN         0x03
#define EASE_QUARTIC_OUT        0x43
#define EASE_QUARTIC_IN_OUT     0x83
#define EASE_QUARTIC_BOUNCING   0xC3
#endif
 
#if defined(ENABLE_EASE_USER)
#define EASE_USER_DIRECT        0x06
#define EASE_USER_IN            0x06
#define EASE_USER_OUT           0x46
#define EASE_USER_IN_OUT        0x86
#define EASE_USER_BOUNCING      0xC6
#endif
 
#define EASE_DUMMY_MOVE         0x07 // can be used as delay
 
#if defined(ENABLE_EASE_SINE)
#define EASE_SINE_IN            0x08
#define EASE_SINE_OUT           0x48
#define EASE_SINE_IN_OUT        0x88
#define EASE_SINE_BOUNCING      0xC8
#endif
 
#if defined(ENABLE_EASE_CIRCULAR)
#define EASE_CIRCULAR_IN        0x09
#define EASE_CIRCULAR_OUT       0x49
#define EASE_CIRCULAR_IN_OUT    0x89
#define EASE_CIRCULAR_BOUNCING  0xC9
#endif
 
#if defined(ENABLE_EASE_BACK)
#define EASE_BACK_IN            0x0A
#define EASE_BACK_OUT           0x4A
#define EASE_BACK_IN_OUT        0x8A
#define EASE_BACK_BOUNCING      0xCA
#endif
 
#if defined(ENABLE_EASE_ELASTIC)
#define EASE_ELASTIC_IN         0x0B
#define EASE_ELASTIC_OUT        0x4B
#define EASE_ELASTIC_IN_OUT     0x8B
#define EASE_ELASTIC_BOUNCING   0xCB
#endif
 
#if defined(ENABLE_EASE_BOUNCE)
// the coded function is an OUT function
#define EASE_BOUNCE_IN          0x4C // call OUT function inverse
#define EASE_BOUNCE_OUT         0x0C // call OUT function direct
#endif
 
#if defined(ENABLE_EASE_PRECISION)
#define EASE_PRECISION_IN       0x0D // Negative bounce for movings from above (go in to origin)
#define EASE_PRECISION_OUT      0x4D // Positive bounce for movings from below (go out from origin)
#endif
 
// !!! Must be without trailing comment and closed by @formatter:on
// @formatter:off
extern const char easeTypeLinear[]     PROGMEM;
#if !defined(PROVIDE_ONLY_LINEAR_MOVEMENT)
extern const char easeTypeQuadratic[]  PROGMEM;
extern const char easeTypeCubic[]      PROGMEM;
extern const char easeTypeQuartic[]    PROGMEM;
extern const char easeTypePrecision[]  PROGMEM;
extern const char easeTypeUser[]       PROGMEM;
extern const char easeTypeDummy[]      PROGMEM;
#  if !defined(DISABLE_COMPLEX_FUNCTIONS)
extern const char easeTypeSine[]       PROGMEM;
extern const char easeTypeCircular[]   PROGMEM;
extern const char easeTypeBack[]       PROGMEM;
extern const char easeTypeElastic[]    PROGMEM;
extern const char easeTypeBounce[]     PROGMEM;
#  endif // !defined(DISABLE_COMPLEX_FUNCTIONS)
#endif // !defined(PROVIDE_ONLY_LINEAR_MOVEMENT)
// @formatter:on
extern const char *const easeTypeStrings[] PROGMEM;
 
// some PCA9685 specific constants
#define PCA9685_GENERAL_CALL_ADDRESS 0x00
#define PCA9685_SOFTWARE_RESET          6
#define PCA9685_DEFAULT_ADDRESS      0x40
#define PCA9685_MAX_CHANNELS           16 // 16 PWM channels on each PCA9685 expansion module
#define PCA9685_MODE1_REGISTER        0x0
#define PCA9685_MODE_1_RESTART          7
#define PCA9685_MODE_1_AUTOINCREMENT    5
#define PCA9685_MODE_1_SLEEP            4
#define PCA9685_MODE1_EXTCLK            6  // Use EXTCLK pin clock
#define PCA9685_FIRST_PWM_REGISTER   0x06
#define PCA9685_PRESCALE_REGISTER    0xFE
#if !defined(PCA9685_ACTUAL_CLOCK_FREQUENCY)
// See chapter 2 and 5 of the PCA9685 Datasheet "25 MHz typical internal oscillator requires no external components"
#define PCA9685_ACTUAL_CLOCK_FREQUENCY   25000000L // 25 MHz this is the default frequency
#endif
 
#define PCA9685_PRESCALER_FOR_20_MS ((PCA9685_ACTUAL_CLOCK_FREQUENCY /(4096L * 50)) - 1) //for 25 MHz it is: 121 / 0x79 for 20 ms or 50 Hz
 
// to be used as values for parameter bool aStartUpdateByInterrupt
#define START_UPDATE_BY_INTERRUPT           true
#define DO_NOT_START_UPDATE_BY_INTERRUPT    false
 
#define mCurrentMicrosecondsOrUnits         mLastTargetMicrosecondsOrUnits // to be backwards compatible
/*
 * Size is 46 bytes RAM per servo
 */
class ServoEasing
#if (!defined(USE_PCA9685_SERVO_EXPANDER) || defined(USE_SERVO_LIB)) && !defined(USE_LIGHTWEIGHT_SERVO_LIBRARY)
        : public Servo
#endif
{
public:
 
#if defined(USE_PCA9685_SERVO_EXPANDER)
#  if defined(ARDUINO_SAM_DUE)
    ServoEasing(uint8_t aPCA9685I2CAddress, TwoWire *aI2CClass = &Wire1);
#  else
#    if defined(USE_SOFT_I2C_MASTER)
    ServoEasing(uint8_t aPCA9685I2CAddress);
#    else
    ServoEasing(uint8_t aPCA9685I2CAddress, TwoWire *aI2CClass = &Wire);
#    endif
#  endif
    void I2CInit();
    void PCA9685Reset();
    void PCA9685Init();
    void PCA9685Init(uint32_t aActualPCA9685ClockFrequencyHertz);
    void PCA9685InitWithExternalClock(uint32_t aExternalClockFrequencyHertz);
    void I2CWriteByte(uint8_t aAddress, uint8_t aData);
    void setPWM(uint16_t aPWMOffValueAsUnits);
    void setPWM(uint16_t aPWMOnStartValueAsUnits, uint16_t aPWMPulseDurationAsUnits);
    // main mapping functions for us to PCA9685 Units (20000/4096 = 4.88 us) and back
    int MicrosecondsToPCA9685Units(int aMicroseconds);
    int PCA9685UnitsToMicroseconds(int aPCA9685Units);
#endif // defined(USE_PCA9685_SERVO_EXPANDER)
 
    ServoEasing();
 
    uint8_t attach(int aPin);
    uint8_t attach(int aPin, int aInitialDegreeOrMicrosecond);
    uint8_t attachWithTrim(int aPin, int aTrimDegreeOrMicrosecond, int aInitialDegreeOrMicrosecond);
    // Here no units accepted, only microseconds!
    uint8_t attach(int aPin, int aMicrosecondsForServo0Degree, int aMicrosecondsForServo180Degree);
    uint8_t attach(int aPin, int aInitialDegreeOrMicrosecond, int aMicrosecondsForServo0Degree, int aMicrosecondsForServo180Degree);
    uint8_t attachWithTrim(int aPin, int aTrimDegreeOrMicrosecond, int aInitialDegreeOrMicrosecond,
            int aMicrosecondsForServo0Degree, int aMicrosecondsForServo180Degree);
    uint8_t attach(int aPin, int aMicrosecondsForServoLowDegree, int aMicrosecondsForServoHighDegree, int aServoLowDegree,
            int aServoHighDegree);
    uint8_t attach(int aPin, int aInitialDegreeOrMicrosecond, int aMicrosecondsForServoLowDegree,
            int aMicrosecondsForServoHighDegree, int aServoLowDegree, int aServoHighDegree);
    uint8_t attachWithTrim(int aPin, int aTrimDegreeOrMicrosecond, int aInitialDegreeOrMicrosecond,
            int aMicrosecondsForServoLowDegree, int aMicrosecondsForServoHighDegree, int aServoLowDegree, int aServoHighDegree);
 
    uint8_t reattach();
    void detach(); // No servo signal is generated for a detached servo / the output is constant LOW.
    void setReverseOperation(bool aOperateServoReverse); // You should call it before using setTrim, or better use attach function with 6 parameters
 
    void setTrim(int aTrimDegreeOrMicrosecond, bool aDoWrite = false);
    void _setTrimMicrosecondsOrUnits(int aTrimMicrosecondsOrUnits, bool aDoWrite = false);
 
#if defined(ENABLE_MIN_AND_MAX_CONSTRAINTS)
    void setMaxConstraint(int aMaxDegreeOrMicrosecond);
    void setMinConstraint(int aMinDegreeOrMicrosecond);
    void setMinMaxConstraint(int aMinDegreeOrMicrosecond, int aMaxDegreeOrMicrosecond);
#endif
 
#if !defined(PROVIDE_ONLY_LINEAR_MOVEMENT)
    void setEasingType(uint_fast8_t aEasingType);
    uint_fast8_t getEasingType();
 
    float callEasingFunction(float aPercentageOfCompletion);            // used in update()
 
#  if defined(ENABLE_EASE_USER)
    void registerUserEaseInFunction(float (*aUserEaseInFunction)(float aPercentageOfCompletion, void *aUserDataPointer),
            void *aUserDataPointer = nullptr);
    void setUserDataPointer(void *aUserDataPointer);
#  endif
#endif
 
    void write(int aTargetDegreeOrMicrosecond);     // Apply trim and reverse to the value and write it direct to the Servo library.
    void _writeMicrosecondsOrUnits(int aTargetMicrosecondsOrUnits);
 
    void easeTo(int aTargetDegreeOrMicrosecond);                                   // blocking move to new position using mLastSpeed
    void easeTo(int aTargetDegreeOrMicrosecond, uint_fast16_t aDegreesPerSecond);  // blocking move to new position using speed
    void easeToD(int aTargetDegreeOrMicrosecond, uint_fast16_t aMillisForMove);    // blocking move to new position using duration
 
    bool setEaseTo(int aTargetDegreeOrMicrosecond);              // shortcut for startEaseTo(..,..,DO_NOT_START_UPDATE_BY_INTERRUPT)
    bool setEaseTo(unsigned int aTargetDegreeOrMicrosecond);     // shortcut for startEaseTo(..,..,DO_NOT_START_UPDATE_BY_INTERRUPT)
    bool setEaseTo(int aTargetDegreeOrMicrosecond, uint_fast16_t aDegreesPerSecond); // shortcut for startEaseTo(..,..,DO_NOT_START_UPDATE_BY_INTERRUPT)
    bool startEaseTo(int aTargetDegreeOrMicrosecond);        // shortcut for startEaseTo(aDegree, mSpeed, START_UPDATE_BY_INTERRUPT)
    bool startEaseTo(unsigned int aTargetDegreeOrMicrosecond); // shortcut for startEaseTo(aDegree, mSpeed, START_UPDATE_BY_INTERRUPT)
    bool startEaseTo(int aTargetDegreeOrMicrosecond, uint_fast16_t aDegreesPerSecond, bool aStartUpdateByInterrupt =
    START_UPDATE_BY_INTERRUPT);
    bool startEaseTo(unsigned int aTargetDegreeOrMicrosecond, uint_fast16_t aDegreesPerSecond, bool aStartUpdateByInterrupt =
    START_UPDATE_BY_INTERRUPT);
    bool setEaseToD(int aTargetDegreeOrMicrosecond, uint_fast16_t aDegreesPerSecond); // shortcut for startEaseToD(..,..,DO_NOT_START_UPDATE_BY_INTERRUPT)
    bool setEaseToD(unsigned int aTargetDegreeOrMicrosecond, uint_fast16_t aDegreesPerSecond); // shortcut for startEaseToD(..,..,DO_NOT_START_UPDATE_BY_INTERRUPT)
    bool startEaseToD(int aTargetDegreeOrMicrosecond, uint_fast16_t aMillisForMove, bool aStartUpdateByInterrupt =
    START_UPDATE_BY_INTERRUPT);
    bool startEaseToD(unsigned int aTargetDegreeOrMicrosecond, uint_fast16_t aMillisForMove, bool aStartUpdateByInterrupt =
    START_UPDATE_BY_INTERRUPT);
    // The float versions
    void write(float aTargetDegreeOrMicrosecond);   // Apply trim and reverse to the value and write it direct to the Servo library.
 
    void easeTo(float aTargetDegreeOrMicrosecond);                                 // blocking move to new position using mLastSpeed
    void easeTo(float aTargetDegreeOrMicrosecond, uint_fast16_t aDegreesPerSecond);  // blocking move to new position using speed
    void easeToD(float aTargetDegreeOrMicrosecond, uint_fast16_t aMillisForMove);    // blocking move to new position using duration
 
    bool setEaseTo(float aTargetDegreeOrMicrosecond);            // shortcut for startEaseTo(..,..,DO_NOT_START_UPDATE_BY_INTERRUPT)
    bool setEaseTo(float aTargetDegreeOrMicrosecond, uint_fast16_t aDegreesPerSecond); // shortcut for startEaseTo(..,..,DO_NOT_START_UPDATE_BY_INTERRUPT)
    bool startEaseTo(float aTargetDegreeOrMicrosecond);      // shortcut for startEaseTo(aDegree, mSpeed, START_UPDATE_BY_INTERRUPT)
    bool startEaseTo(float aTargetDegreeOrMicrosecond, uint_fast16_t aDegreesPerSecond, bool aStartUpdateByInterrupt =
    START_UPDATE_BY_INTERRUPT);
    bool setEaseToD(float aTargetDegreeOrMicrosecond, uint_fast16_t aDegreesPerSecond); // shortcut for startEaseToD(..,..,DO_NOT_START_UPDATE_BY_INTERRUPT)
    bool startEaseToD(float aTargetDegreeOrMicrosecond, uint_fast16_t aMillisForMove, bool aStartUpdateByInterrupt =
    START_UPDATE_BY_INTERRUPT);
 
    bool noMovement(uint_fast16_t aMillisToWait);                                       // stay at the position for aMillisToWait
 
    void setSpeed(uint_fast16_t aDegreesPerSecond);                            // This speed is taken if no speed argument is given.
    uint_fast16_t getSpeed();
 
    void stop();
    void pause();
    void resumeWithInterrupts();
    void resumeWithoutInterrupts();
    bool update();
 
    void setTargetPositionReachedHandler(void (*aTargetPositionReachedHandler)(ServoEasing*));
 
    // To be compatible to Servo library
    int readMicroseconds();
    int read();
 
    int getCurrentAngle();
    int getCurrentMicroseconds();
    int getDeltaMicrosecondsOrUnits();
    int getEndMicrosecondsOrUnits();
    int getEndMicrosecondsOrUnitsWithTrim();
    int getMillisForCompleteMove();
    bool isMoving();
    bool isMovingAndCallYield()
            __attribute__ ((deprecated ("Replaced by isMoving(). Often better to use areInterruptsActive() instead.")));
 
    int MicrosecondsOrUnitsToDegree(int aMicrosecondsOrUnits);
    int MicrosecondsToDegree(int aMicroseconds);
    int MicrosecondsOrUnitsToMicroseconds(int aMicrosecondsOrUnits);
    int DegreeOrMicrosecondToMicrosecondsOrUnits(int aDegreeOrMicrosecond);
    int DegreeOrMicrosecondToMicrosecondsOrUnits(float aDegreeOrMicrosecond);
//    int DegreeToMicrosecondsOrUnits(float aDegree);
    int DegreeToMicrosecondsOrUnitsWithTrimAndReverse(int aDegree);
 
    int applyTrimAndReverseToTargetMicrosecondsOrUnits(int aTargetMicrosecondsOrUnits);
    void print(Print *aSerial, bool doExtendedOutput = true); // Print dynamic and static info
    void printDynamic(Print *aSerial, bool doExtendedOutput = true);
    void printStatic(Print *aSerial);
    void printExtra(Print *aSerial);
 
    static void printEasingType(Print *aSerial, uint_fast8_t aEasingType);
 
    /*
     * Included easing functions
     */
    static float QuadraticEaseIn(float aPercentageOfCompletion);
    static float CubicEaseIn(float aPercentageOfCompletion);
    static float QuarticEaseIn(float aPercentageOfCompletion);
    static float SineEaseIn(float aPercentageOfCompletion);
    static float CircularEaseIn(float aPercentageOfCompletion);
    static float BackEaseIn(float aPercentageOfCompletion);
    static float ElasticEaseIn(float aPercentageOfCompletion);
    // Non symmetric function
    static float EaseOutBounce(float aPercentageOfCompletion);
    // Special non static function
    float LinearWithQuadraticBounce(float aPercentageOfCompletion);
 
    /*
     * Convenience function
     */
#if defined(USE_PCA9685_SERVO_EXPANDER)
#  if defined(__AVR__)
    bool InitializeAndCheckI2CConnection(Print *aSerial) __attribute__ ((deprecated ("Use initializeAndCheckI2CConnection()")));
    bool initializeAndCheckI2CConnection(Print *aSerial); // Using Print class saves 95 bytes flash
#  else
    bool InitializeAndCheckI2CConnection(Stream *aSerial); __attribute__ ((deprecated ("Use initializeAndCheckI2CConnection()")));
    bool initializeAndCheckI2CConnection(Stream *aSerial); // Print class has no flush() here
#  endif
#endif
 
    /*
     * Static functions
     */
    static bool areInterruptsActive(); // The recommended test if at least one servo is moving yet.
 
    volatile int mLastTargetMicrosecondsOrUnits; 
    int mStartMicrosecondsOrUnits;  
    int mEndMicrosecondsOrUnits;    
    int mDeltaMicrosecondsOrUnits;  
 
    uint_fast16_t mSpeed; 
 
#if !defined(PROVIDE_ONLY_LINEAR_MOVEMENT)
    uint8_t mEasingType; // EASE_LINEAR, EASE_QUADRATIC_IN_OUT, EASE_CUBIC_IN_OUT, EASE_QUARTIC_IN_OUT
#  if defined(ENABLE_EASE_USER)
    void *UserDataPointer;
    float (*mUserEaseInFunction)(float aPercentageOfCompletion, void *aUserDataPointer);
#  endif
#endif
 
    volatile bool mServoMoves; // Servo is moving on next call to update()
 
#if defined(USE_PCA9685_SERVO_EXPANDER)
#  if defined(USE_SERVO_LIB)
    // Here we can have both types of servo connections
    bool mServoIsConnectedToExpander; // to distinguish between different using microseconds or PWM units and appropriate write functions
#  endif
    uint8_t mPCA9685I2CAddress;
#  if !defined(USE_SOFT_I2C_MASTER)
    TwoWire *mI2CClass;
#  endif
#endif
    uint8_t mServoPin; 
 
    uint8_t mServoIndex; 
 
    uint32_t mMillisAtStartMove;
    uint_fast16_t mMillisForCompleteMove;
#if !defined(DISABLE_PAUSE_RESUME)
    bool mServoIsPaused;
    uint32_t mMillisAtStopMove;
#endif
 
    bool mOperateServoReverse; 
#if defined(ENABLE_MIN_AND_MAX_CONSTRAINTS)
    int mMaxMicrosecondsOrUnits; 
    int mMinMicrosecondsOrUnits; 
#endif
    int mTrimMicrosecondsOrUnits; 
 
    int mServo0DegreeMicrosecondsOrUnits;   // default is DEFAULT_MICROSECONDS_FOR_0_DEGREE (544)
    int mServo180DegreeMicrosecondsOrUnits; // default is DEFAULT_MICROSECONDS_FOR_180_DEGREE (2400)
 
    void (*TargetPositionReachedHandler)(ServoEasing*);  
 
    static volatile bool sInterruptsAreActive; 
 
    static uint_fast8_t sServoArrayMaxIndex; 
    static ServoEasing *ServoEasingArray[MAX_EASING_SERVOS];
    static float ServoEasingNextPositionArray[MAX_EASING_SERVOS];
    /*
     * Macros for backward compatibility
     */
#define areInterruptsActive() ServoEasing::areInterruptsActive()
#define sServoArray ServoEasing::ServoEasingArray
#define sServoNextPositionArray ServoEasing::ServoEasingNextPositionArray
 
};
 
/*
 * Functions working on all servos in the list
 */
void writeAllServos(int aTargetDegreeOrMicrosecond);
void setSpeedForAllServos(uint_fast16_t aDegreesPerSecond);
#if defined(va_arg)
void setIntegerDegreeForAllServos(uint_fast8_t aNumberOfValues, va_list *aDegreeValues);
void setFloatDegreeForAllServos(uint_fast8_t aNumberOfValues, va_list *aDegreeValues);
#endif
#if defined(va_start)
void setDegreeForAllServos(uint_fast8_t aNumberOfValues, ...)
        __attribute__ ((deprecated ("Please use setIntegerDegreeForAllServos().")));
void setIntegerDegreeForAllServos(uint_fast8_t aNumberOfValues, ...);
void setFloatDegreeForAllServos(uint_fast8_t aNumberOfValues, ...);
#endif
 
bool setEaseToForAllServos();
bool setEaseToForAllServos(uint_fast16_t aDegreesPerSecond);
bool setEaseToDForAllServos(uint_fast16_t aMillisForMove);
void setEaseToForAllServosSynchronizeAndStartInterrupt();
void setEaseToForAllServosSynchronizeAndStartInterrupt(uint_fast16_t aDegreesPerSecond);
void synchronizeAllServosAndStartInterrupt(bool aStartUpdateByInterrupt = START_UPDATE_BY_INTERRUPT, bool aSynchronizeToMinimumDuration = false);
 
#if !defined(PROVIDE_ONLY_LINEAR_MOVEMENT)
void setEasingTypeForAllServos(uint_fast8_t aEasingType);
void setEasingTypeForMultipleServos(uint_fast8_t aNumberOfServos, uint_fast8_t aEasingType);
#endif
 
// blocking wait functions
void updateAndWaitForAllServosToStop();
bool delayAndUpdateAndWaitForAllServosToStop(unsigned long aMillisDelay, bool aTerminateDelayIfAllServosStopped = false);
void setEaseToForAllServosSynchronizeAndWaitForAllServosToStop();
void setEaseToForAllServosSynchronizeAndWaitForAllServosToStop(uint_fast16_t aDegreesPerSecond);
void synchronizeAndEaseToArrayPositions() __attribute__ ((deprecated ("Please use setEaseToForAllServosSynchronizeAndWait().")));
void synchronizeAndEaseToArrayPositions(uint_fast16_t aDegreesPerSecond)
        __attribute__ ((deprecated ("Please use setEaseToForAllServosSynchronizeAndWait().")));
void synchronizeAllServosStartAndWaitForAllServosToStop();
 
void printArrayPositions(Print *aSerial);
bool isOneServoMoving();
void stopAllServos();
void resumeWithInterruptsAllServos();
void resumeWithoutInterruptsAllServos();
bool updateAllServos();
 
void enableServoEasingInterrupt();
#if defined(__AVR_ATmega328P__)
void setTimer1InterruptMarginMicros(uint16_t aInterruptMarginMicros);
#endif
void disableServoEasingInterrupt();
 
int clipDegreeSpecial(uint_fast8_t aDegreeToClip);
 
//extern float (*sEaseFunctionArray[])(float aPercentageOfCompletion);
 
// Static convenience function
#if defined(__AVR__)
bool checkI2CConnection(uint8_t aI2CAddress, Print *aSerial); // Using Print class saves 95 bytes flash
#else
bool checkI2CConnection(uint8_t aI2CAddress, Stream *aSerial); // Print class has no flush() here
#endif
 
#if !defined(STR_HELPER) && !defined(STR)
#define STR_HELPER(x) #x
#define STR(x) STR_HELPER(x)
#endif
 
/*
 *
 * Version 3.6.0 - 02/2026
 * - Renamed macro REFRESH_INTERVAL_MILLIS to SERVO_REFRESH_INTERVAL_MICROS.
 * - Added new functions PCA9685Init(uint32_t aActualPCA9685ClockFrequencyHertz) and PCA9685InitWithExternalClock(uint32_t aExternalClockFrequencyHertz).
 * - Added parameter bool aSynchronizeToMinimumDuration to synchronizeAllServosAndStartInterrupt().
 *
 * Version 3.5.0 - 9/2025
 * - Fixed serious bug in reattach();
 * - Renamed InitializeAndCheckI2CConnection() to initializeAndCheckI2CConnection().
 * - Renamed applyTrimAndreverseToTargetMicrosecondsOrUnits() to applyTrimAndReverseToTargetMicrosecondsOrUnits().
 * - Housekeeping.
 *
 * Version 3.4.0 - 10/2024
 * - LightweightServo support for ATmega2560.
 * - Renamed mCurrentMicrosecondsOrUnits to mLastTargetMicrosecondsOrUnits to make clear, that trim and reverse is NOT applied to this value.
 * - Changed DISABLE_MIN_AND_MAX_CONSTRAINTS to ENABLE_MIN_AND_MAX_CONSTRAINTS. Constraint checking is now disabled by default.
 * - candorgander fixed a bug in printEasingType() for non AVR platforms.
 *
 * Version 3.3.0 - 08/2024
 * - Added functions `setEaseTo()`, `setEaseToD()`, `startEaseTo()` and `startEaseToD()` with first parameter as `unsigned int` to avoid compiler errors `call of overloaded 'startEaseTo(unsigned int...`.
 * - Added functions read() and readMicroseconds() to be compatible to Servo library.
 * - Added function reattach() without parameters to be used after detach().
 * - Added `USE_USER_PROVIDED_SERVO_LIB` macro.
 *
 * Version 3.2.1 - 03/2023
 * - Renamed function `setDegreeForAllServos()` to `setIntegerDegreeForAllServos()` and added function `setFloatDegreeForAllServos()`.
 *
 * Version 3.2.0 - 02/2023
 * - ATmega4808 support added.
 * - Added function `getCurrentMicroseconds()`.
 * - Improved many and added workaround for ESP32 bug in while loops in examples.
 * - Added `PCA9685_ACTUAL_CLOCK_FREQUENCY` macro.
 * - Renamed function `synchronizeAndEaseToArrayPositions()` to `setEaseToForAllServosSynchronizeAndWaitForAllServosToStop()`.
 *
 * Version 3.1.0 - 08/2022
 * - SAMD51 support by Lutz Aumueller.
 * - Added support to pause and resume and `DISABLE_PAUSE_RESUME`.
 * - Fixed some bugs for PCA9685 expander introduced in 3.0.0.
 * - Feather Huzzah support with the help of Danner Claflin.
 * - Added `ENABLE_EXTERNAL_SERVO_TIMER_HANDLER` macro.
 *
 * Version 3.0.0 - 05/2022
 * - Added target reached callback functionality, to enable multiple movements without loop control.
 * - Changed `ENABLE_MICROS_AS_DEGREE_PARAMETER` to `DISABLE_MICROS_AS_DEGREE_PARAMETER` thus enabling micros as parameter by default.
 * - Fixed some bugs for micros as parameter.
 * - Changed constants for easing types.
 * - Additional parameter aUserDataPointer for user easing function.
 * - New easing type `PRECISION`.
 * - New function `printEasingType()`.
 * - Easing functions are converted to static member functions now.
 * - Easing types can be disabled individually.
 * - Improved PCA9685 handling / support for SoftI2CMaster.
 * - Changed default for parameter `doWrite` for `setTrim()` from `false` to `true`.
 * - Added min and max constraints for servo write() and `DISABLE_MIN_AND_MAX_CONSTRAINTS`.
 *
 * Version 2.4.1 - 02/2022
 * - RP2040 support added.
 * - Fix for Nano Every interrupts.
 *
 * Version 2.4.0 - 10/2021
 * - New `attach()` functions with initial degree parameter to be written immediately. This replaces the `attach()` and `write()` combination at setup.
 * - Renamed ServoEasing.cpp.h to ServoEasing.hpp and LightweightServo.cpp to LightweightServo.hpp.
 *
 * Version 2.3.4 - 02/2021
 * - ENABLE_MICROS_AS_DEGREE_PARAMETER also available for PCA9685 expander.
 * - Moved `sServoArrayMaxIndex`, `sServoNextPositionArray` and `sServoArray` to `ServoEasing::sServoArrayMaxIndex`, `ServoEasing::ServoEasingNextPositionArray` and `ServoEasing::ServoEasingArray`.
 *
 * Version 2.3.3 - 11/2020
 * - Added compile option `ENABLE_MICROS_AS_DEGREE_PARAMETER` to allow usage of microseconds instead of degree as function arguments for all functions using degrees as argument.
 * - Improved LightweightServo API.
 *
 * Version 2.3.2 - 9/2020
 * - Removed blocking wait for ATmega32U4 Serial in examples.
 * - Improved output for Arduino Serial Plotter.
 *
 * Version 2.3.1 - 9/2020
 * - Fixed wrong timer selection for `STM32F1xx` / `ARDUINO_ARCH_STM32`.
 * - Documentation.
 *
 * Version 2.3.0 - 7/2020
 * - Fixed EASE_LINEAR formula bug introduced with 2.0.0 for 32 bit CPU's.
 * - Added `stop()`, `continueWithInterrupts()` and `continueWithoutInterrupts()` functions.
 *
 * Version 2.2.0 - 7/2020
 * - ATmega4809 (Uno WiFi Rev 2, Nano Every) support.
 * - Corrected position of macro for MAX_EASING_SERVOS.
 *
 * Version 2.1.1 - 6/2020
 * - Fixed bug in detach of first servo.
 *
 * Version 2.1.0 - 6/2020
 * - Teensy support.
 *
 * Version 2.0.0 - 5/2020
 * - `PCA9685_Expander` and standard Servos can be controlled simultaneously by defining `USE_SERVO_LIB`.
 * - Changed some types to _fast types
 * - Standardize pins for all examples
 *
 * Version 1.6.1 - 5/2020
 * - Fix bug for **Arduino SAMD** boards.
 *
 * Version 1.6.0 - 4/2020
 * - Added support of Apollo3 boards.
 * - Print library version in examples.
 *
 * Version 1.5.2 - 3/2020
 * - More examples using `areInterruptsActive()`.
 * - Added support of Arduino SAMD boards.
 *
 * Version 1.5.1 - 3/2020
 * - Added support for STM32 cores of Arduino Board manager. Seen in the Arduino IDE as "Generic STM32F1 series" from STM32 Boards.
 * - Inserted missing `Wire.begin()` in setup of `PCA9685_Expander` example.
 * - In `isMovingAndCallYield()` yield() only called/required for an ESP8266.
 * - New function `areInterruptsActive()`, especially for ESP32.
 *
 * Version 1.5.0 - 2/2020
 * - Use type `Print *` instead of `Stream *`.
 * - New LightweightServoExample.
 * - Added function `delayAndUpdateAndWaitForAllServosToStop()`.
 * - Added Arduino Due support by using timer 8.
 * - New PCA9685_ExpanderFor32Servos example.
 *
 * Version 1.4.3 - 12/2019
 * - Improved detach() handling.
 * - Initialize mSpeed explicitly to 0 in constructor. On an ESP8266 it was NOT initialized to 0 :-(.
 *
 * Version 1.4.2 - 11/2019
 * - Improved INVALID_SERVO handling.
 * - Speed 0 (not initialized) handling.
 * - Fixed bug in ThreeServos example.
 *
 * Version 1.4.1 - 11/2019
 * - Improved documentation and definitions for continuous rotating servo. Thanks to Eebel!
 * - Improved support and documentation for generating Arduino Serial Plotter output.
 * - Support of STM32F1 / BluePill boards.
 *
 * Version 1.4.0 - 11/2019
 * - setTrim has additional parameter 'doWrite' which is default 'false' in contrast to older versions, where a write was always performed.
 * - New attach( aPin,  aMicrosecondsForServoLowDegree,  aMicrosecondsForServoHighDegree,  aServoLowDegree,  aServoHighDegree) function for arbitrary mapping of servo degree to servo pulse width.
 * - Order of Servos in 'sServoArray[]' now depends from order of calling attach() and not from order of declaration.
 * - New example for continuous rotating servo.
 * - Support for multiple PCA9685 expander.
 *
 * Version 1.3.1 - 6/2019
 * - Added detach() function.
 *
 * Version 1.3.0 - 6/2019
 * - Added ESP32 support by using ESP32Servo.h and Ticker.h instead of Servo.h timer interrupts.
 * - Changed degree parameter and values from uint8_t to integer to support operating a servo from -90 to + 90 degree with 90 degree trim.
 * - RobotArmControl + QuadrupedControl examples refactored.
 * - Extended SpeedTest example. Now also able to change the width of the refresh period.
 * - Changed "while" to "for" loops to avoid a gcc 7.3.0 atmel6.3.1 bug.
 *
 * Version 1.2 - 5/2019
 * - Added ESP8266 support by using Ticker instead of timer interrupts for ESP.
 * - AsymetricEasing example overhauled.
 *
 * Version 1.1 - 4/2019
 * - corrected sine, circular, back and elastic IN functions.
 * - easeTo() and write() store their degree parameter now also in sServoNextPositionArray.
 * - added setSpeed(), getSpeed(), setSpeedForAllServos().
 * - added easeTo(uint8_t aDegree) and setEaseTo(uint8_t aDegree).
 * - added setEaseToForAllServos(), setEaseToForAllServosSynchronizeAndStartInterrupt(), synchronizeAndEaseToArrayPositions().
 * - added getEndMicrosecondsOrUnits(), getDeltaMicrosecondsOrUnits().
 * - added setDegreeForAllServos(uint8_t aNumberOfValues, va_list * aDegreeValues),setDegreeForAllServos(uint8_t aNumberOfValues, ...).
 * - added compile switch PROVIDE_ONLY_LINEAR_MOVEMENT to save additional 1500 bytes program memory if enabled.
 * - added convenience function clipDegreeSpecial().
 */
 
#if !defined(_SERVO_EASING_HPP) && !defined(SUPPRESS_HPP_WARNING)
#warning You probably must change the line #include "ServoEasing.h" to #include "ServoEasing.hpp" in your ino file or define SUPPRESS_HPP_WARNING before the include to suppress this warning.
#endif
 
#endif // _SERVO_EASING_H