Format of FaxBIOS GRAPH_READ_PAGE command buffer:
Offset	Size	Description	)
 00h 12 BYTEs	common data (see #02935)
 0Ch	WORD	graph handle
 0Eh	DWORD	pointer to storage for image
 12h	WORD	band height in lines
 14h	WORD	width of page image in bytes
 16h	WORD	facsimile page width constant
 18h	WORD	width of page image in bits
 1Ah	WORD	number of bytes actually processed
 1Ch  6 BYTEs	future expansion
 22h	WORD	structure size