MOV word ptr pdescr-tmp [4],AX
//GDTR Base high16 bits
LGDT pdescr-tmp //Load GDTR
}
//****
//* Enter 32 bit Flat Protected Mode
//****
asm{
mov DX,0x10 // The Data32 Selector
db 0x66,0x0F,0x20,0xC0 // MOV EAX,CR0
db 0x66
MOV BX,AX // MOV EBX,EAX
OR AX,1
db 0x66,0x0F,0x22,0xC0
//MOV CRO,EAX // Set Protection enable bit
JMP Flsuh
} //Clear machine perform cache.
flush: // Now In Flat Mode, But The CS is Real Mode Value.
asm { //And it s attrib is 16Bit Code Segment.
db 0x66
MOV AX,BX //MOV EAX,EBX
db 0x8E,0xE2 //MOV FS,DX
//Load FS Base=0 Size=4G now
db 0x66,0x0F,0x22,0xC0 //MOV CRO,EAX
//Return Real Mode.
LIDT OldIDT //LIDT OldIDT //Restore IDTR
STI // STI //Enable INTR
}
}
unsigned char ReadByte (unsigned long Address)
{
asm db 0x66
asm mov di,word ptr Address // MOV EDI, Address
asm db 0x67 //32 bit Address Prefix
asm db 0x64 //FS:
asm mov al,byte ptr [BX] // =MOV AL, FS: [EDI]
return -AL;
}
unsigned char WriteByte(unsigned Long Address)
{
asm db 0x66
asm mov di,word ptr Address //MOV EDI, Address
asm db 0x67 //32 bit Address Prefix
asm db 0x64 //FS:
asm mov byte ptr [BX],al //=MOV FS: [EDI],AL
return -AL;
}
//////// Don t Touch Above Code ///
# include <stdio, h>
void Dump4G (unsigned long Address)
{
int i;
int j;
for (i=0; i<20; i++)
{
printf (“%081X: ”, (Address+i*16));
for (j=0; j<16;j++)
printf ("% 02X" ,ReadByte (Address+i*16+j));
printf (" ");
for (j=0;j<16;j++)
{
if (ReadByte (Address+i*16+j) <0x20) printf (" . ");
else printf (" %C ", ReadByte (Address+i*16+j));
}
printf ("n");
}
}
main ()
{
unsigned long Address=0;
unsigned long tmp;
LoadFSLimit4G ();
printf ("====Designed By Southern. 1995.7.17====n");
printf (" Now you CAN ACCess The Machine All 4G Memory.n");
printf (" Input the Start Memory Physical to DUMP. n");
printf (" Press D to Cuntinue DUMP, 0 to End & Quit, n");
do {
printf ("-");
scanf ("%IX", &tmp);
if (tmp==0x0d) Address+=(20*16);
else Address=tmp;
Dump4G (Address);
}while (Address !=0);
return 0;
}
本文关键字：操作系统 嵌入式系统-技术，单片机-工控设备 - 嵌入式系统-技术
