#include <tos.h>


typedef struct
	{	long magic;
		long freq;
		int  r_seg;
	}	SEGM_HEADER;
	
const long IdentFreq[]  = {'6.25', '12.5', '25.0', '50.0'};

/* the DMA play back frequency */
extern int PlayFreq;



int LoadSegm(int f, int *rep_segm, long length, long *segm)
{long *s, freq;
 char *image;
 SEGM_HEADER head;
 
 	Fread(f, sizeof(SEGM_HEADER), &head); /* read the header */
 	if (head.magic != 'SEGM')
 		return 3;

	s = IdentFreq;  /* get playback frequency from file */
	freq = 0;
	while(*s++ != head.freq)
		if (freq++ > 4)
			return 2;
		
	PlayFreq	= 128 + (int)freq;
	
	*rep_segm = head.r_seg; /* get repeat segment from file */

	Fread(f, length, segm); /* read file into memory */
	
/* find address of the sample image */
	s = segm; 
	while (*s != -1)
		s += 2;
		
	image = (char *)(s + 2);
	
/* Now fixup the sequence table, (offsets -> abs. addreses) */
	while (*segm != -1)
	{	*segm = (long)(image + *segm);
		segm += 2;
	}
	
	return 0;
}