page    58,132
title   INSTALL  Copyright (c) 1986 COMPAQ Computer Corp.
;******************************************************************************
;
;   Name:       INSTALL
;
;   Group:      PATCH
;
;   Revision:   1.00
;
;   Date:       June 26, 1986
;
;   Author:     M P Vaughan
;               S M Dawson 8/31/87
;
;******************************************************************************
;
;  Changes:
;
;    DATE     REVISION                  DESCRIPTION
;  --------   --------   ------------------------------------------------------
;  06/26/86     1.00     Original.
;   8/31/87     1.1      Changed to fix up Int 10 Plasma ROM bug
;
;******************************************************************************
;
;  Functional Description:
;
;       This module installs a terminate and stay resident routine for INT 9
;       to enable the featuere of toggling the underline feature for dual
;       scan monitors and COMPAQ vdu controllers.
;
;
;       RETURNS:
;               AL = 00h        Installation successful
;               AL = 01h        Installation failed
;
;******************************************************************************
;
;******************************************************************************
;
;  Equates
;
;******************************************************************************
;
STANDARDOUT     equ     01h
CR              equ     0Dh
LF              equ     0Ah
DOS             equ     21h
;
page
patch   segment byte public 'PATCH'
        assume  cs:patch,ds:patch
;
;******************************************************************************
;
;  Externals
;
;******************************************************************************
;
;                              External routines
;
        extrn   _new10:near             ; New INT 10h entry point.
;
;                                External data
;
        extrn   oldint:dword            ; Old INT 10h interrupt vector
;
page
;******************************************************************************
;                     Install - install new INT10 routine
;******************************************************************************
;
        public  install
;
install         proc
;
        push    ds
        push    cs
        pop     ds                      ; Save initial value of DS
;
        mov     ax,3510h                ; Get old interrupt vector
        int     DOS
;
        mov     word ptr [oldint],bx  ; Save old offset, segment
        mov     word ptr [oldint+2],es
;
        mov     dx,offset _new10        ; Set new INT 15h interrupt
        mov     ax,2510h
        int     DOS
        pop     ds
 
        ret                             ; Return to calling procedure
install endp
patch   ends
        end     install