INT 14 - I1541 - TEST IF 1541 CABLE CONNECTED                                   
	AX = 4001h
Return: CF clear if connected
	    BL = LPTAbbreviation for Line PrinTer. number where 1541 cable is connected (1..3)
	CF set if cable not connected
Desc:	scan all the LPTAbbreviation for Line PrinTer. ports searching for the adapter cable
SeeAlso: AX=4000h