internal byte[] GetApiPacket()
{
ByteWriter bw = new ByteWriter(ByteOrder.BigEndian);
WriteApiBytes(bw);
byte[] bytes = bw.GetBytes();
ushort length = (ushort)bytes.Length;
XBeeChecksum checksum = new XBeeChecksum();
checksum.AddBytes(bytes);
bw = new ByteWriter(length + 1 /* start byte */ + 2 /* bytes for length */ + 1 /* checksum byte */, ByteOrder.BigEndian);
bw.Write(PACKET_STARTBYTE);
bw.Write(length);
bw.Write(bytes);
bw.Write(checksum.Compute());
return(bw.GetBytes());
}
private bool CheckLengthAndCrc()
{
// can't be to short
if (_readBuffer.Length < 4)
{
return(false);
}
int length = (_readBuffer.ReadByte() << 8) + _readBuffer.ReadByte();
// real length = start(1) + length.length(2) + length parameter + crc(1)
if ((length + 4) > _readBuffer.Length)
{
return(false);
}
XBeeChecksum checksum = new XBeeChecksum();
for (int i = 0; i < length; i++)
{
checksum.AddByte((byte)_readBuffer.ReadByte());
}
checksum.Compute();
bool result = checksum.Verify((byte)_readBuffer.ReadByte());
#if (LOG && !MF && !WindowsCE)
if (!result)
{
Console.WriteLine("++ --> BAD CRC!!");
}
#endif
return(result);
}
