/// <summary>
/// Write sector data, including the CRC, to the stream. The stream must be positioned at the first byte of the sector
/// payload data.
/// </summary>
/// <param name="data">Sector data buffer.</param>
/// <param name="offset">Offset of the first byte of sector data into the data buffer.</param>
/// <param name="length">Size of the sector data.</param>
private void WriteSectorData(byte[] data, int offset, int length)
{
Sync();
var blockId = trackStream.ReadByte();
if (blockId == -1)
{
throw new DiskImageFormatException("Sector data not found after sector address mark");
}
if (blockId != DataAddressMark)
{
throw new DiskImageFormatException(String.Format("Unexpected block type {0}", blockId));
}
var crc = new Crc16Ccitt();
crc.Add(0xa1);
crc.Add(0xa1);
crc.Add(0xa1);
crc.Add(DataAddressMark);
for (int i = 0; i < length; i++)
{
crc.Add(data[offset + i]);
}
trackStream.Write(data, offset, length);
trackStream.WriteByte((byte)((crc.Crc >> 8) & 0xff));
trackStream.WriteByte((byte)(crc.Crc & 0xff));
}
public void CalculateCrc()
{
var data = new byte[] {0xa1, 0xa1, 0xa1, 0xfe, 0x14, 0x00, 0x09, 0x01};
var crcExpected = (uint) 0xa2f3;
var crc = new Crc16Ccitt();
var crcActual = crc.Add(data);
Assert.AreEqual(crcExpected, crcActual);
}
private uint ComputeCrc()
{
var crc = new Crc16Ccitt();
crc.Add(HfeTrack.SyncMark);
crc.Add(HfeTrack.SyncMark);
crc.Add(HfeTrack.SyncMark);
crc.Add(HfeTrack.DataAddressMark);
foreach (byte t in data)
{
crc.Add(t);
}
return(crc.Crc);
}
private uint ComputeCrc()
{
var crc = new Crc16Ccitt();
crc.Add(HfeTrack.SyncMark);
crc.Add(HfeTrack.SyncMark);
crc.Add(HfeTrack.SyncMark);
crc.Add(HfeTrack.IdAddressMark);
crc.Add((byte)Track);
crc.Add((byte)Head);
crc.Add((byte)Sector);
crc.Add(ConvertToEncodedSize(Size));
return(crc.Crc);
}
private uint ComputeCrc()
{
var crc = new Crc16Ccitt();
crc.Add(HfeTrack.SyncMark);
crc.Add(HfeTrack.SyncMark);
crc.Add(HfeTrack.SyncMark);
crc.Add(HfeTrack.DataAddressMark);
foreach (byte t in data)
crc.Add(t);
return crc.Crc;
}
private uint ComputeCrc()
{
var crc = new Crc16Ccitt();
crc.Add(HfeTrack.SyncMark);
crc.Add(HfeTrack.SyncMark);
crc.Add(HfeTrack.SyncMark);
crc.Add(HfeTrack.IdAddressMark);
crc.Add((byte) Track);
crc.Add((byte) Head);
crc.Add((byte) Sector);
crc.Add(ConvertToEncodedSize(Size));
return crc.Crc;
}
