dda.h

#ifndef _DDA_H
#define _DDA_H

#include <stdint.h>

#include "config.h"

#ifdef ACCELERATION_REPRAP
#  ifdef ACCELERATION_RAMPING
#    error Cant use ACCELERATION_REPRAP and ACCELERATION_RAMPING together.
#  endif
#endif

/*
  types
*/
typedef struct {
// TODO: We should really make up a loop for all axes.
  int32_t X, Y, Z;
  uint32_t F;
} TARGET;

typedef struct {
  // bresenham counters
  int32_t x_counter; 
  int32_t y_counter; 
  int32_t z_counter; 

  // step counters
  uint32_t x_steps; 
  uint32_t y_steps; 
  uint32_t z_steps; 

#ifdef ACCELERATION_RAMPING

  uint32_t step_no;
  uint32_t c;
  int32_t n;
#endif
#ifdef ACCELERATION_TEMPORAL
  uint32_t x_time; 
  uint32_t y_time; 
  uint32_t z_time; 
  uint32_t all_time; 
#endif
} MOVE_STATE;

typedef struct {
  TARGET endpoint;
  union {
    struct {
      // status fields
      uint8_t nullmove:1; 
      uint8_t live:1; 
#ifdef ACCELERATION_REPRAP
      uint8_t accel:1; 
#endif
      // directions
      uint8_t x_direction:1; 
      uint8_t y_direction:1; 
      uint8_t z_direction:1; 
    };
    uint8_t allflags;  
  };
  // distances
  uint32_t x_delta; 
  uint32_t y_delta; 
  uint32_t z_delta; 

  uint32_t total_steps;
  uint32_t c; 

#ifdef ACCELERATION_REPRAP
  uint32_t end_c; 
  int32_t n; 
#endif
#ifdef ACCELERATION_RAMPING

  uint32_t rampup_steps;
  uint32_t rampdown_steps;
  uint32_t c_min;
#endif
#ifdef ACCELERATION_TEMPORAL
  uint32_t x_step_interval; 
  uint32_t y_step_interval; 
  uint32_t z_step_interval; 
  uint8_t axis_to_step;    
#endif

  uint8_t endstop_check; 
  uint8_t endstop_stop_cond; 
} DDA;

/*
  variables
*/
extern TARGET startpoint;
extern TARGET startpoint_steps;
extern TARGET current_position;

/*
  methods
*/
// initialize dda structures
void dda_init(void);

// distribute a new startpoint
void dda_new_startpoint(void);

// create a DDA
void dda_create(DDA *dda, TARGET *target);

// start a created DDA (called from timer interrupt)
void dda_start(DDA *dda) __attribute__ ((hot));

// DDA takes one step (called from timer interrupt)
void dda_step(DDA *dda) __attribute__ ((hot));

// update current_position
void update_current_position(void);

#endif /* _DDA_H */

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