isvesa.c

BIOS emulator and interface to Realmode X86 Emulator Library Can emulate a PCI Graphic Controller V

/****************************************************************************
*
*					SciTech OS Portability Manager Library
*
*  ========================================================================
*
*    The contents of this file are subject to the SciTech MGL Public
*    License Version 1.0 (the "License"); you may not use this file
*    except in compliance with the License. You may obtain a copy of
*    the License at http://www.scitechsoft.com/mgl-license.txt
*
*    Software distributed under the License is distributed on an
*    "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
*    implied. See the License for the specific language governing
*    rights and limitations under the License.
*
*    The Original Code is Copyright (C) 1991-1998 SciTech Software, Inc.
*
*    The Initial Developer of the Original Code is SciTech Software, Inc.
*    All Rights Reserved.
*
*  ========================================================================
*
* Language:		ANSI C
* Environment:	any
*
* Description:  Test program to check the ability to allocate real mode
*				memory and to call real mode interrupt handlers such as
*				the VESA VBE BIOS from protected mode. Compile and link
*				with the appropriate command line for your DOS extender.
*
*				Functions tested:	PM_getVESABuf()
*									PM_mapRealPointer()
*									PM_int86x()
*
****************************************************************************/

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "pmapi.h"

/* SuperVGA information block */

#pragma pack(1)

typedef struct {
	char    VESASignature[4];       /* 'VESA' 4 byte signature          */
	short   VESAVersion;            /* VBE version number               */
	ulong	OEMStringPtr;           /* Far pointer to OEM string        */
	ulong	Capabilities;           /* Capabilities of video card       */
	ulong	VideoModePtr;           /* Far pointer to supported modes   */
	short   TotalMemory;            /* Number of 64kb memory blocks     */
	char    reserved[236];          /* Pad to 256 byte block size       */
	} VgaInfoBlock;

#pragma pack()

int main(void)
{
	RMREGS			regs;
	RMSREGS			sregs;
	VgaInfoBlock	vgaInfo;
	ushort			*mode;
	uint			vgLen;
	uchar			*vgPtr;
	unsigned 		r_vgseg,r_vgoff;

	printf("Program running in ");
	switch (PM_getModeType()) {
		case PM_realMode:
			printf("real mode.\n\n");
			break;
		case PM_286:
			printf("16 bit protected mode.\n\n");
			break;
		case PM_386:
			printf("32 bit protected mode.\n\n");
			break;
		}

	/* Allocate a 256 byte block of real memory for communicating with
	 * the VESA BIOS.
	 */
	if ((vgPtr = PM_getVESABuf(&vgLen,&r_vgseg,&r_vgoff)) == NULL) {
		printf("Unable to allocate VESA memory buffer!\n");
		exit(1);
		}

	/* Call the VESA VBE to see if it is out there */
	regs.x.ax = 0x4F00;
	regs.x.di = r_vgoff;
	sregs.es = r_vgseg;
	memcpy(vgPtr,"VBE2",4);
	PM_int86x(0x10, &regs, &regs, &sregs);
	memcpy(&vgaInfo,vgPtr,sizeof(VgaInfoBlock));
	if (regs.x.ax == 0x4F && strncmp(vgaInfo.VESASignature,"VESA",4) == 0) {
		printf("VESA VBE version %d.%d BIOS detected\n\n",
			vgaInfo.VESAVersion >> 8, vgaInfo.VESAVersion & 0xF);
		printf("Available video modes:\n");
		mode = PM_mapRealPointer(vgaInfo.VideoModePtr >> 16, vgaInfo.VideoModePtr & 0xFFFF);
		while (*mode != 0xFFFF) {
			printf("    %04hXh (%08X)\n", *mode, (int)mode);
			mode++;
			}
		}
	else
		printf("VESA VBE not found\n");
	return 0;
}