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extern void outPort(unsigned short port, unsigned char data);
extern unsigned char inPort(unsigned short port);

bool HardDisk::ReadDisk(unsigned char *buffer, unsigned short NoOfSectors, unsigned __int32 LBA, unsigned char drive)
{
	unsigned short base_port = 0;
	if(drive > 1)
	{
		base_port = 0x0170;
		drive-=2;
	}
	else
		base_port = 0x01F0;

	LBA = LBA & 0x0FFFFFFF;

	unsigned char status = inPort(base_port+6);	
	// I dont want to declare another variable to hold the drive/head register data.
	status = status | (drive << 4);
	outPort(base_port + 6, status);
	status = inPort(base_port + 7);	// delay
	status = inPort(base_port + 7);	// delay
	status = inPort(base_port + 7);	// delay
	status = inPort(base_port + 7);	// delay
	outPort(base_port+7, 0x08);	// reset disk
	while(true)
	{
		if((status & IDE_READY) == IDE_READY)
			break;
		if(((status & IDE_ERROR) == IDE_ERROR) || ((status & IDE_DRIVEFAULT) == IDE_DRIVEFAULT))
			outPort(base_port+7, 0x08);
	}

	while(NoOfSectors > 0)
	{
		status = inPort(base_port + 6);
		status = status | 0x40 | (unsigned char)(LBA >> 24);
		outPort(base_port + 6, status);
		outPort(base_port + 2, 0x01);
		outPort(base_port + 3, (unsigned char)LBA);
		outPort(base_port + 4, (unsigned char)(LBA >> 8));
		outPort(base_port + 5, (unsigned char)(LBA >> 16));
		outPort(base_port + 7, 0x20);

		while(true)
		{
			status = inPort(base_port + 7);
			if(((status & IDE_READY) == IDE_READY) && ((status & IDE_BUSY) == 0) && ((status & IDE_DATAREADY) == IDE_DATAREADY))
				break;
			if(((status & IDE_ERROR) == IDE_ERROR) || ((status & IDE_DRIVEFAULT) == IDE_DRIVEFAULT))
				outPort(base_port+7, 0x08);
		}
		__asm
		{
			mov edi, dword ptr [buffer]
			mov dx, word ptr [base_port]
			mov ecx, 0x100
			cld
			rep insw
		}
		NoOfSectors -= 1;
		buffer += 0x200;
		LBA += 1;
		__asm
		{
			nop
			nop
			nop
			nop
			nop
		}
	}
	return true;
}