marlin/Marlin/planner.h

/*
  planner.h - buffers movement commands and manages the acceleration profile plan
  Part of 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/>.
*/

// This module is to be considered a sub-module of stepper.c. Please don't include 
// this file from any other module.

#ifndef planner_h
#define planner_h

#include "Configuration.h"

// This struct is used when buffering the setup for each linear movement "nominal" values are as specified in 
// the source g-code and may never actually be reached if acceleration management is active.
typedef struct {
  // Fields used by the bresenham algorithm for tracing the line
  long steps_x, steps_y, steps_z, steps_e;  // Step count along each axis
  long step_event_count;                    // The number of step events required to complete this block
  volatile long accelerate_until;                    // The index of the step event on which to stop acceleration
  volatile long decelerate_after;                    // The index of the step event on which to start decelerating
  volatile long acceleration_rate;                   // The acceleration rate used for acceleration calculation
  unsigned char direction_bits;             // The direction bit set for this block (refers to *_DIRECTION_BIT in config.h)
#ifdef ADVANCE
  long advance_rate;
  volatile long initial_advance;
  volatile long final_advance;
  float advance;
#endif

  // Fields used by the motion planner to manage acceleration
  float speed_x, speed_y, speed_z, speed_e;          // Nominal mm/minute for each axis
  float nominal_speed;                               // The nominal speed for this block in mm/min  
  float millimeters;                                 // The total travel of this block in mm
  float entry_speed;
  float acceleration;                                // acceleration mm/sec^2

  // Settings for the trapezoid generator
  long nominal_rate;                                 // The nominal step rate for this block in step_events/sec 
  volatile long initial_rate;                        // The jerk-adjusted step rate at start of block  
  volatile long final_rate;                          // The minimal rate at exit
  long acceleration_st;                              // acceleration steps/sec^2
  volatile char busy;
} block_t;
      
// Initialize the motion plan subsystem      
void plan_init();

// Add a new linear movement to the buffer. x, y and z is the signed, absolute target position in 
// millimaters. Feed rate specifies the speed of the motion.
void plan_buffer_line(float x, float y, float z, float e, float feed_rate);

// Set position. Used for G92 instructions.
void plan_set_position(float x, float y, float z, float e);

// Called when the current block is no longer needed. Discards the block and makes the memory
// availible for new blocks.
void plan_discard_current_block();

// Gets the current block. Returns NULL if buffer empty
block_t *plan_get_current_block();

void check_axes_activity();

extern unsigned long minsegmenttime;
extern float max_feedrate[4]; // set the max speeds
extern float axis_steps_per_unit[4];
extern long max_acceleration_units_per_sq_second[4]; // Use M201 to override by software
extern float minimumfeedrate;
extern float acceleration;         // Normal acceleration mm/s^2  THIS IS THE DEFAULT ACCELERATION for all moves. M204 SXXXX
extern float retract_acceleration; //  mm/s^2   filament pull-pack and push-forward  while standing still in the other axis M204 TXXXX
extern float max_xy_jerk; //speed than can be stopped at once, if i understand correctly.
extern float max_z_jerk;
extern float mintravelfeedrate;
extern unsigned long axis_steps_per_sqr_second[NUM_AXIS];

#endif