PAGE	,132
	TITLE	DXOEM.ASM  -- Dos Extender OEM Interface

; Copyright (c) Microsoft Corporation 1988-1991. All Rights Reserved.

;***********************************************************************
;
;	DXOEM.ASM	- DOS Extender OEM Interface
;
;-----------------------------------------------------------------------
;
; This module contains the routines that may need to be modified by OEMs
; when adding new device/interface support to the Microsoft 286 DOS
; Extender portion of Windows/286.  There are four routines contained
; in this module:
;
;	InitializeOEM	- called during DOSX initialization
;
;	SuspendOEM	- called when the protected mode app is about
;			  to be suspended (currently when running a
;			  standard DOS 'old' app from Windows).
;
;	ResumeOEM	- called when the protected mode app is about
;			  to be resumed (currently when returning from
;			  a standard DOS 'old' app to Windows).
;
;	TerminateOEM	- called during DOSX termination
;
; Note: when this module refers to the 'OEM layer,' it is refering to
; the 286 DOS Extender device drivers, API mappers, etc., not the
; Windows OEM layer.
;
;-----------------------------------------------------------------------
;
;  06/28/89 jimmat  Original version.
;  11/29/90 amitc   Removed SuspendOEM/ResumeOEM - not required for 3.1
;  11/29/90 amitc   Moved call to 'InitLowHeap' from here to DXNETBIO.ASM
;
;***********************************************************************

	.286p

; -------------------------------------------------------
;           INCLUDE FILE DEFINITIONS
; -------------------------------------------------------

	.xlist
	.sall
include     segdefs.inc
include     gendefs.inc
include     pmdefs.inc
	.list

; -------------------------------------------------------
;           GENERAL SYMBOL DEFINITIONS
; -------------------------------------------------------


; -------------------------------------------------------
;           EXTERNAL SYMBOL DEFINITIONS
; -------------------------------------------------------

	extrn	InitNetMapper:NEAR
	extrn	TermNetMapper:NEAR
	extrn	ReleaseLowHeap:NEAR

; -------------------------------------------------------
;           DATA SEGMENT DEFINITIONS
; -------------------------------------------------------

DXDATA	segment

	extrn	NetHeapSize:WORD

DXDATA	ends


; -------------------------------------------------------
;           CODE SEGMENT VARIABLES
; -------------------------------------------------------

DXCODE  segment

DXCODE  ends

DXPMCODE    segment

DXPMCODE    ends

; -------------------------------------------------------
	subttl OEM Initialization Routine
        page
; -------------------------------------------------------
;	    OEM INITIALIZATION ROUTINE
; -------------------------------------------------------

DXPMCODE    segment
        assume  cs:DXPMCODE

;--------------------------------------------------------
;   InitializeOEM --  This routine is called during DOSX initialization
;	in order to initialize the OEM layer (device drivers, API
;	mappers, etc.).  It expectes to be called late enough in the
;	initialization process that other interrupt mapping functions
;	(like Int 21h) are available.
;
;	This routine is called in protected mode, and can enable/disable
;	interrupts if it so requires.
;
;   Input:  none
;   Output: none
;   Errors: none
;   Uses:   ax, all others preserved

	assume	ds:DGROUP,es:NOTHING,ss:NOTHING
	public	InitializeOEM

InitializeOEM	proc	near

; Initialize the NetBios mapper.

	mov	ax,NetHeapSize		;don't initialize if net heap
	or	ax,ax			;  size set to zero
	jz	@f

	call	InitNetMapper		;initialize the NetBIOS mapper--CY set
					;  if NetBIOS not installed
@@:
	ret

InitializeOEM	endp

; -------------------------------------------------------

DXPMCODE    ends

; -------------------------------------------------------
	subttl OEM Termination Routine
        page
; -------------------------------------------------------
;	       OEM TERMINATION ROUTINE
; -------------------------------------------------------

DXCODE	segment
	assume	cs:DXCODE

; -------------------------------------------------------
;   TerminateOEM --  This routine is called during DOSX termination
;	to disable the OEM layer.
;
;   Note:  This routine must is called in REAL MODE!  If some termination
;	code must run in protected mode, the routine must switch to
;	protected mode itself, and switch back to real mode before
;	returning.
;
;   Input:  none
;   Output: none
;   Errors: none
;   Uses:   ax,bx,cx,dx,si,di,es
;

	assume	ds:DGROUP,es:NOTHING,ss:NOTHING
	public	TerminateOEM

TerminateOEM	proc	near

	call	TermNetMapper		;terminate the NetBIOS mapper

	call	ReleaseLowHeap		;  and release the low net heap

	ret

TerminateOEM	endp

; -------------------------------------------------------

DXCODE	ends
;****************************************************************
        end