marlin/Marlin/src/HAL/servo.h

/**
 * Marlin 3D Printer Firmware
 * Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
 * Based on Sprinter and grbl.
 * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
 *
 * This program 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/>.
 *
 */

/**
  servo.h - Interrupt driven Servo library for Arduino using 16 bit timers- Version 2
  Copyright (c) 2009 Michael Margolis.  All right reserved.

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.

  This library 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
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

/**

  A servo is activated by creating an instance of the Servo class passing the desired pin to the attach() method.
  The servos are pulsed in the background using the value most recently written using the write() method

  Note that analogWrite of PWM on pins associated with the timer are disabled when the first servo is attached.
  Timers are seized as needed in groups of 12 servos - 24 servos use two timers, 48 servos will use four.
  The sequence used to seize timers is defined in timers.h

  The methods are:

   Servo - Class for manipulating servo motors connected to Arduino pins.

   attach(pin )  - Attaches a servo motor to an i/o pin.
   attach(pin, min, max  ) - Attaches to a pin setting min and max values in microseconds
   default min is 544, max is 2400

   write()     - Sets the servo angle in degrees.  (invalid angle that is valid as pulse in microseconds is treated as microseconds)
   writeMicroseconds() - Sets the servo pulse width in microseconds
   read()      - Gets the last written servo pulse width as an angle between 0 and 180.
   readMicroseconds() - Gets the last written servo pulse width in microseconds. (was read_us() in first release)
   attached()  - Returns true if there is a servo attached.
   detach()    - Stops an attached servos from pulsing its i/o pin.
   move(angle) - Sequence of attach(0), write(angle),
                   With DEACTIVATE_SERVOS_AFTER_MOVE wait SERVO_DELAY and detach.
 */

#ifndef servo_h
#define servo_h

#if IS_32BIT_TEENSY
  #include "HAL_TEENSY35_36/HAL_Servo_Teensy.h" // Teensy HAL uses an inherited library
#else

#include <inttypes.h>

#if defined(ARDUINO_ARCH_AVR) || defined(ARDUINO_ARCH_SAM)
  // we're good to go
#else
  #error "This library only supports boards with an AVR or SAM3X processor."
#endif

#define Servo_VERSION           2     // software version of this library

class Servo {
  public:
    Servo();
    int8_t attach(int pin);            // attach the given pin to the next free channel, set pinMode, return channel number (-1 on fail)
    int8_t attach(int pin, int min, int max); // as above but also sets min and max values for writes.
    void detach();
    void write(int value);             // if value is < 200 it is treated as an angle, otherwise as pulse width in microseconds
    void writeMicroseconds(int value); // write pulse width in microseconds
    void move(int value);              // attach the servo, then move to value
                                       // if value is < 200 it is treated as an angle, otherwise as pulse width in microseconds
                                       // if DEACTIVATE_SERVOS_AFTER_MOVE wait SERVO_DELAY, then detach
    int read();                        // returns current pulse width as an angle between 0 and 180 degrees
    int readMicroseconds();            // returns current pulse width in microseconds for this servo (was read_us() in first release)
    bool attached();                   // return true if this servo is attached, otherwise false

  private:
    uint8_t servoIndex;               // index into the channel data for this servo
    int8_t min;                       // minimum is this value times 4 added to MIN_PULSE_WIDTH
    int8_t max;                       // maximum is this value times 4 added to MAX_PULSE_WIDTH
};

#endif // !TEENSY

#endif