INT 7A - IBM 3270 Workstation Program API - OPERATOR INFORMATION AREA

	AH = 09h
	BX = 8020h
	CX = 00FFh
	DX = ID of OIAM
	AL = service
	    01h read Operator Information Area
	    02h read OIA subset
	ES:DI -> control block
Return: ???
Note: the OIA is the 25th line on the Host session