Format of HSCOORD parameter block:
Offset	Size	Description	)
 00h	WORD	0003h (length of following data)
 02h	BYTE	coordinate format
		bits 7-4: bytes per coordinate
		bits 3-0: fraction bytes in coordinate
 03h	BYTE	relative coordinates format
		bits 7-4: bytes per coordinate
		bits 3-0: fraction bytes in coordinate
 04h	BYTE	number of dimensions (2-4)