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/* $XConsortium: mach8.c,v 1.1 94/03/28 21:09:56 dpw Exp $ */
/*
* Copyright 1992 by Alan Hourihane, Wigan, England.
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation, and that the name of Alan Hourihane not be used in
* advertising or publicity pertaining to distribution of the software without
* specific, written prior permission. Alan Hourihane makes no representations
* about the suitability of this software for any purpose. It is provided
* "as is" without express or implied warranty.
*
* ALAN HOURIHANE DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
* EVENT SHALL ALAN HOURIHANE BE LIABLE FOR ANY SPECIAL, INDIRECT OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
* DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
* TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*
* Author: Alan Hourihane, alanh@logitek.co.uk, version 0.1beta
*
* David Wexelblat, dwex@goblin.org, version 0.2beta
* (dual banks)
* David Wexelblat, version 0.3beta (back to 1 bank)
*/
/*
* These are here the very lowlevel VGA bankswitching routines.
* The segment to switch to is passed via %eax. Only %eax and %edx my be used
* without saving the original contents.
*/
#include "assyntax.h"
FILE("tvga8900bank.s")
AS_BEGIN
SEG_DATA
SEG_TEXT
ALIGNTEXT4
GLOBL GLNAME(TVGA8900SetReadWrite)
GLOBL GLNAME(TVGA8900SetRead)
GLOBL GLNAME(TVGA8900SetWrite)
GLNAME(TVGA8900SetReadWrite):
GLNAME(TVGA8900SetRead):
GLNAME(TVGA8900SetWrite):
MOV_B (AL,AH)
MOV_B (CONST(0x0E),AL)
XOR_B (CONST(0x02),AH)
MOV_L (CONST(0x3C4),EDX)
OUT1_W (DX)
RET
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