private void DoIdentifyDrive(byte index)
{
driveInfo[index].Present = false;
//Send the identify command to the selected drive
DeviceHeadPort.Write8((byte)((index == 0) ? 0xA0 : 0xB0));
SectorCountPort.Write8(0);
LBALowPort.Write8(0);
LBAMidPort.Write8(0);
LBAHighPort.Write8(0);
CommandPort.Write8(IDECommand.IdentifyDrive);
if (StatusPort.Read8() == 0)
{
//Drive doesn't exist
return;
}
//Wait until a ready status is present
if (!WaitForReadyStatus())
{
return; //There's no ready status, this drive doesn't exist
}
if (LBAMidPort.Read8() != 0 && LBAHighPort.Read8() != 0) //Check if the drive is ATA
{
//In this case the drive is ATAPI
//HAL.DebugWriteLine("Device " + index.ToString() + " not ATA");
return;
}
//Wait until the identify data is present (256x16 bits)
if (!WaitForIdentifyData())
{
//HAL.DebugWriteLine("Device " + index.ToString() + " ID error");
return;
}
//An ATA drive is present
driveInfo[index].Present = true;
//Read the identification info
var info = new DataBlock(512);
for (uint ix = 0; ix < 256; ix++)
{
info.SetUShort(ix * 2, DataPort.Read16());
}
//Find the addressing mode
var lba28SectorCount = info.GetUInt(IdentifyDrive.MaxLBA28);
AddressingMode aMode = AddressingMode.NotSupported;
if ((info.GetUShort(IdentifyDrive.CommandSetSupported83) & 0x200) == 0x200) //Check the LBA48 support bit
{
aMode = AddressingMode.LBA48;
driveInfo[index].MaxLBA = info.GetUInt(IdentifyDrive.MaxLBA48);
}
else if (lba28SectorCount > 0) //LBA48 not supported, check LBA28
{
aMode = AddressingMode.LBA28;
driveInfo[index].MaxLBA = lba28SectorCount;
}
driveInfo[index].AddressingMode = aMode;
//HAL.DebugWriteLine("Device " + index.ToString() + " present - MaxLBA=" + driveInfo[index].MaxLBA.ToString());
}