INT 7A R - AutoCAD Device Interface - DISPLAY - INITIALIZE (INIT1)
        AX = 0001h
        BX = configuration
        CX = interface level (0001h)
Return: AX = status
            0000h initialization failed
            0001h pre-v4.0 driver initialized successfully
            0003h post-v3.1 driver initialized successfully (driver truncates
                          excessivly long packets)
        BX = width of graphics area in pixels, or 0000h if using packet
                          communication
        DX:CX -> packet-mode entry point
SeeAlso: AX=0001h,AX=0200h,AX=07D0h,INT 61/AX=0007h"OPTIMA",INT 78"AutoCAD"
SeeAlso: INT 79/AX=0001h,INT 7B/AX=8001h"AutoCAD",INT 7C"AutoShade"

Call packet-mode entry point with:
STACK:  DWORD   pointer to request packet
        WORD    length of packet

Format of request packet:
Offset  Size    Description
 00h    WORD    function number (00h-45h for Compaq VGADI41.EXE)

.