public static byte[] makePacket(byte[] rawData, byte source, byte destination, bool addError = false)
{
int packetsAmount = rawData.Length / bytesPerPacket;
if ((rawData.Length % bytesPerPacket) > 0)
{
packetsAmount++;
}
packets.Clear();
for (int packetNumber = 0; packetNumber < packetsAmount; packetNumber++)
{
CRC8.clearValue();
insertEndOfPacket();
insertByte(source);
CRC8.updateChecksumm(source);
insertByte(destination);
CRC8.updateChecksumm(destination);
int currentPosition = packetNumber * bytesPerPacket;
for (int byteNumber = 0; byteNumber < bytesPerPacket; byteNumber++)
{
byte currentByte;
if (currentPosition + byteNumber >= rawData.Length)
{
break;
}
else
{
currentByte = rawData[currentPosition + byteNumber];
}
insertByte(currentByte);
CRC8.updateChecksumm(currentByte);
}
if (addError)
{
if (packets[packets.Count - 1])
{
packets[packets.Count - 1] = false;
}
else
{
packets[packets.Count - 1] = true;
}
}
insertByte(CRC8.Value);
insertEndOfPacket();
}
return(bitListToByteArray());
}
public static byte[] extractFromPacket(byte[] packet)
{
int bitsDeleted = 0;
bool bitDeleted = false;
packets.Clear();
for (int byteNumber = 1; byteNumber < packet.Length - 1; byteNumber++)
{
for (int bitNumber = 7; bitNumber >= 0; bitNumber--)
{
packets.Add(((packet[byteNumber] >> bitNumber) & 1) == 1);
if (!bitDeleted && checkForSequence(Operation.Extract))
{
bitDeleted = true;
bitsDeleted++;
continue;
}
bitDeleted = false;
}
}
int bitsToDelete = 8 - (bitsDeleted % 8);
if (bitsToDelete != 8)
{
for (int i = 0; i < bitsToDelete; i++)
{
packets.RemoveAt(packets.Count - 1);
}
}
byte expectedChecksumm = extractByte((packets.Count / 8) - 1);
for (int i = 0; i < 8; i++)
{
packets.RemoveAt(packets.Count - 1);
}
byte[] extractedMessage = bitListToByteArray();
CRC8.clearValue();
CRC8.updateChecksumm(extractedMessage);
byte checksumm = CRC8.Value;
if (checksumm != expectedChecksumm)
{
return(null);
}
return(extractedMessage);
}
private static void insertCheckSum(byte[] data, int currentPos)
{
CRC8.clearValue();
for (int i = 0; i < bytesPerPacket; i++)
{
if (currentPos + i >= data.Length)
{
break;
}
CRC8.updateChecksumm(data[currentPos + i]);
}
insertByte(CRC8.Value);
}
