text: /**
   * 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/>.
   *
   */
  
  /**
   * stepper.h - stepper motor driver: executes motion plans of planner.c using the stepper motors
   * Derived from Grbl
   *
   * Copyright (c) 2009-2011 Simen Svale Skogsrud
   *
   * Grbl 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.
   *
   * Grbl 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 Grbl.  If not, see <http://www.gnu.org/licenses/>.
   */
  
  #ifndef STEPPER_H
  #define STEPPER_H
  
  #include "planner.h"
  #include "speed_lookuptable.h"
  #include "stepper_indirection.h"
  #include "language.h"
  #include "types.h"
  
  class Stepper;
  extern Stepper stepper;
  
  #define ENABLE_STEPPER_DRIVER_INTERRUPT()  SBI(TIMSK1, OCIE1A)
  #define DISABLE_STEPPER_DRIVER_INTERRUPT() CBI(TIMSK1, OCIE1A)
  
  // intRes = intIn1 * intIn2 >> 16
  // uses:
  // r26 to store 0
  // r27 to store the byte 1 of the 24 bit result
  #define MultiU16X8toH16(intRes, charIn1, intIn2) \
    asm volatile ( \
                   "clr r26 \n\t" \
                   "mul %A1, %B2 \n\t" \
                   "movw %A0, r0 \n\t" \
                   "mul %A1, %A2 \n\t" \
                   "add %A0, r1 \n\t" \
                   "adc %B0, r26 \n\t" \
                   "lsr r0 \n\t" \
                   "adc %A0, r26 \n\t" \
                   "adc %B0, r26 \n\t" \
                   "clr r1 \n\t" \
                   : \
                   "=&r" (intRes) \
                   : \
                   "d" (charIn1), \
                   "d" (intIn2) \
                   : \
                   "r26" \
                 )
  
  class Stepper {
  
    public:
  
      static block_t* current_block;  // A pointer to the block currently being traced
  
      #if ENABLED(ABORT_ON_ENDSTOP_HIT_FEATURE_ENABLED)
        static bool abort_on_endstop_hit;
      #endif
  
      #if ENABLED(X_DUAL_ENDSTOPS) || ENABLED(Y_DUAL_ENDSTOPS) || ENABLED(Z_DUAL_ENDSTOPS)
        static bool performing_homing;
      #endif
  
      #if HAS_MOTOR_CURRENT_PWM
        #ifndef PWM_MOTOR_CURRENT
          #define PWM_MOTOR_CURRENT DEFAULT_PWM_MOTOR_CURRENT
        #endif
        static uint32_t motor_current_setting[3];
      #endif
  
      static int16_t cleaning_buffer_counter;
  
    private:
  
      static uint8_t last_direction_bits;        // The next stepping-bits to be output
  
      #if ENABLED(X_DUAL_ENDSTOPS)
        static bool locked_x_motor, locked_x2_motor;
      #endif
      #if ENABLED(Y_DUAL_ENDSTOPS)
        static bool locked_y_motor, locked_y2_motor;
      #endif
      #if ENABLED(Z_DUAL_ENDSTOPS)
        static bool locked_z_motor, locked_z2_motor;
      #endif
  
      // Counter variables for the Bresenham line tracer
      static long counter_X, counter_Y, counter_Z, counter_E;
      static volatile uint32_t step_events_completed; // The number of step events executed in the current block
  
      #if ENABLED(LIN_ADVANCE)
  
        static uint16_t nextMainISR, nextAdvanceISR, eISR_Rate;
        #define _NEXT_ISR(T) nextMainISR = T
        static volatile int e_steps[E_STEPPERS];
        static int final_estep_rate;
        static int current_estep_rate[E_STEPPERS]; // Actual extruder speed [steps/s]
        static int current_adv_steps[E_STEPPERS];  // The amount of current added esteps due to advance.
                                                   // i.e., the current amount of pressure applied
                                                   // to the spring (=filament).
      #else // !LIN_ADVANCE
  
        #define _NEXT_ISR(T) OCR1A = T
  
      #endif // !LIN_ADVANCE
  
      static long acceleration_time, deceleration_time;
      static uint8_t step_loops, step_loops_nominal;
  
      static uint16_t OCR1A_nominal,
                      acc_step_rate; // needed for deceleration start point
  
      static volatile long endstops_trigsteps[XYZ];
      static volatile long endstops_stepsTotal, endstops_stepsDone;
  
      //
      // Positions of stepper motors, in step units
      //
      static volatile long count_position[NUM_AXIS];
  
      //
      // Current direction of stepper motors (+1 or -1)
      //
      static volatile signed char count_direction[NUM_AXIS];
  
      //
      // Mixing extruder mix counters
      //
      #if ENABLED(MIXING_EXTRUDER)
        static long counter_m[MIXING_STEPPERS];
        #define MIXING_STEPPERS_LOOP(VAR) \
          for (uint8_t VAR = 0; VAR < MIXING_STEPPERS; VAR++) \
            if (current_block->mix_event_count[VAR])
      #endif
  
    public:
  
      //
      // Constructor / initializer
      //
      Stepper() { };
  
      //
      // Initialize stepper hardware
      //
      static void init();
  
      //
      // Interrupt Service Routines
      //
  
      static void isr();
  
      #if ENABLED(LIN_ADVANCE)
        static void advance_isr();
        static void advance_isr_scheduler();
      #endif
  
      //
      // Block until all buffered steps are executed
      //
      static void synchronize();
  
      //
      // Set the current position in steps
      //
      static void set_position(const long &a, const long &b, const long &c, const long &e);
      static void set_position(const AxisEnum &a, const long &v);
      static void set_e_position(const long &e);
  
      //
      // Set direction bits for all steppers
      //
      static void set_directions();
  
      //
      // Get the position of a stepper, in steps
      //
      static long position(const AxisEnum axis);
  
      //
      // Report the positions of the steppers, in steps
      //
      static void report_positions();
  
      //
      // Get the position (mm) of an axis based on stepper position(s)
      //
      static float get_axis_position_mm(const AxisEnum axis);
  
      //
      // SCARA AB axes are in degrees, not mm
      //
      #if IS_SCARA
        FORCE_INLINE static float get_axis_position_degrees(const AxisEnum axis) { return get_axis_position_mm(axis); }
      #endif
  
      //
      // The stepper subsystem goes to sleep when it runs out of things to execute. Call this
      // to notify the subsystem that it is time to go to work.
      //
      static void wake_up();
  
      //
      // Wait for moves to finish and disable all steppers
      //
      static void finish_and_disable();
  
      //
      // Quickly stop all steppers and clear the blocks queue
      //
      static void quick_stop();
  
      //
      // The direction of a single motor
      //
      FORCE_INLINE static bool motor_direction(const AxisEnum axis) { return TEST(last_direction_bits, axis); }
  
      #if HAS_DIGIPOTSS || HAS_MOTOR_CURRENT_PWM
        static void digitalPotWrite(const int16_t address, const int16_t value);
        static void digipot_current(const uint8_t driver, const int16_t current);
      #endif
  
      #if HAS_MICROSTEPS
        static void microstep_ms(const uint8_t driver, const int8_t ms1, const int8_t ms2);
        static void microstep_mode(const uint8_t driver, const uint8_t stepping);
        static void microstep_readings();
      #endif
  
      #if ENABLED(X_DUAL_ENDSTOPS)
        FORCE_INLINE static void set_homing_flag_x(const bool state) { performing_homing = state; }
        FORCE_INLINE static void set_x_lock(const bool state) { locked_x_motor = state; }
        FORCE_INLINE static void set_x2_lock(const bool state) { locked_x2_motor = state; }
      #endif
      #if ENABLED(Y_DUAL_ENDSTOPS)
        FORCE_INLINE static void set_homing_flag_y(const bool state) { performing_homing = state; }
        FORCE_INLINE static void set_y_lock(const bool state) { locked_y_motor = state; }
        FORCE_INLINE static void set_y2_lock(const bool state) { locked_y2_motor = state; }
      #endif
      #if ENABLED(Z_DUAL_ENDSTOPS)
        FORCE_INLINE static void set_homing_flag_z(const bool state) { performing_homing = state; }
        FORCE_INLINE static void set_z_lock(const bool state) { locked_z_motor = state; }
        FORCE_INLINE static void set_z2_lock(const bool state) { locked_z2_motor = state; }
      #endif
  
      #if ENABLED(BABYSTEPPING)
        static void babystep(const AxisEnum axis, const bool direction); // perform a short step with a single stepper motor, outside of any convention
      #endif
  
      static inline void kill_current_block() {
        step_events_completed = current_block->step_event_count;
      }
  
      //
      // Handle a triggered endstop
      //
      static void endstop_triggered(const AxisEnum axis);
  
      //
      // Triggered position of an axis in mm (not core-savvy)
      //
      FORCE_INLINE static float triggered_position_mm(const AxisEnum axis) {
        return endstops_trigsteps[axis] * planner.steps_to_mm[axis];
      }
  
      #if HAS_MOTOR_CURRENT_PWM
        static void refresh_motor_power();
      #endif
  
    private:
  
      FORCE_INLINE static unsigned short calc_timer_interval(unsigned short step_rate) {
        unsigned short timer;
  
        NOMORE(step_rate, MAX_STEP_FREQUENCY);
  
        if (step_rate > 20000) { // If steprate > 20kHz >> step 4 times
          step_rate >>= 2;
          step_loops = 4;
        }
        else if (step_rate > 10000) { // If steprate > 10kHz >> step 2 times
          step_rate >>= 1;
          step_loops = 2;
        }
        else {
          step_loops = 1;
        }
  
        NOLESS(step_rate, F_CPU / 500000);
        step_rate -= F_CPU / 500000; // Correct for minimal speed
        if (step_rate >= (8 * 256)) { // higher step rate
          unsigned short table_address = (unsigned short)&speed_lookuptable_fast[(unsigned char)(step_rate >> 8)][0];
          unsigned char tmp_step_rate = (step_rate & 0x00FF);
          unsigned short gain = (unsigned short)pgm_read_word_near(table_address + 2);
          MultiU16X8toH16(timer, tmp_step_rate, gain);
          timer = (unsigned short)pgm_read_word_near(table_address) - timer;
        }
        else { // lower step rates
          unsigned short table_address = (unsigned short)&speed_lookuptable_slow[0][0];
          table_address += ((step_rate) >> 1) & 0xFFFC;
          timer = (unsigned short)pgm_read_word_near(table_address);
          timer -= (((unsigned short)pgm_read_word_near(table_address + 2) * (unsigned char)(step_rate & 0x0007)) >> 3);
        }
        if (timer < 100) { // (20kHz - this should never happen)
          timer = 100;
          MYSERIAL.print(MSG_STEPPER_TOO_HIGH);
          MYSERIAL.println(step_rate);
        }
        return timer;
      }
  
      // Initialize the trapezoid generator from the current block.
      // Called whenever a new block begins.
      FORCE_INLINE static void trapezoid_generator_reset() {
  
        static int8_t last_extruder = -1;
  
        if (current_block->direction_bits != last_direction_bits || current_block->active_extruder != last_extruder) {
          last_direction_bits = current_block->direction_bits;
          last_extruder = current_block->active_extruder;
          set_directions();
        }
  
        deceleration_time = 0;
        // step_rate to timer interval
        OCR1A_nominal = calc_timer_interval(current_block->nominal_rate);
        // make a note of the number of step loops required at nominal speed
        step_loops_nominal = step_loops;
        acc_step_rate = current_block->initial_rate;
        acceleration_time = calc_timer_interval(acc_step_rate);
        _NEXT_ISR(acceleration_time);
  
        #if ENABLED(LIN_ADVANCE)
          if (current_block->use_advance_lead) {
            current_estep_rate[current_block->active_extruder] = ((unsigned long)acc_step_rate * current_block->abs_adv_steps_multiplier8) >> 17;
            final_estep_rate = (current_block->nominal_rate * current_block->abs_adv_steps_multiplier8) >> 17;
          }
        #endif
  
        // SERIAL_ECHO_START();
        // SERIAL_ECHOPGM("advance :");
        // SERIAL_ECHO(current_block->advance/256.0);
        // SERIAL_ECHOPGM("advance rate :");
        // SERIAL_ECHO(current_block->advance_rate/256.0);
        // SERIAL_ECHOPGM("initial advance :");
        // SERIAL_ECHO(current_block->initial_advance/256.0);
        // SERIAL_ECHOPGM("final advance :");
        // SERIAL_ECHOLN(current_block->final_advance/256.0);
      }
  
      #if HAS_DIGIPOTSS || HAS_MOTOR_CURRENT_PWM
        static void digipot_init();
      #endif
  
      #if HAS_MICROSTEPS
        static void microstep_init();
      #endif
  
  };
  
  #endif // STEPPER_H
  