INT 2F U - HP 100LX/200LX - PUSHKEYS - INTERNAL - GET BUFFER ADDRESS            
	AX = C0AFh
Return: ES:DI -> buffer (behind code)
Range:	AH=C0h to AH=FFh, selected by scanning for signature with AL=AEh
SeeAlso: AX=C000h"HP 100LX",AX=C001h"HP 100LX",AX=C0AEh"HP 100LX"