dda_queue.h

#ifndef _DDA_QUEUE
#define _DDA_QUEUE

#include "dda.h"
#include "timer.h"

/*
  variables
*/
// this is the ringbuffer that holds the current and pending moves.
extern uint8_t mb_head;
extern uint8_t mb_tail;
extern DDA movebuffer[MOVEBUFFER_SIZE];

/*
  methods
*/
// queue status methods
uint8_t queue_full(void);
uint8_t queue_empty(void);

// take one step
void queue_step(void);

// add a new target to the queue
void enqueue(TARGET *t);
void enqueue_home(TARGET *t, uint8_t endstop_check, uint8_t endstop_stop_cond);

// called from step timer when current move is complete
void next_move(void) __attribute__ ((hot));

// print queue status
void print_queue(void);

// flush the queue for eg; emergency stop
void queue_flush(void);

// wait for queue to empty
void queue_wait(void);

#endif  /* _DDA_QUEUE */

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