private BufferSpan _ToAdvancedProtocolFrame()
{
var frameLength = 7 + Data.Count;
var frame = new Byte[frameLength];
frame[0] = 0x02;
frame[1] = (Byte)(frameLength >> 8);
frame[2] = (Byte)(frameLength & 0xff);
frame[3] = Address;
frame[4] = (Byte)Command;
Buffer.BlockCopy(
Data.Buffer,
Data.Offset,
frame,
5,
Data.Count
);
var crc = FeigChecksum.Calculate(BufferSpan.From(frame, 0, frameLength - 2));
frame[frameLength - 2] = (Byte)(crc & 0xff);
frame[frameLength - 1] = (Byte)(crc >> 8);
return(BufferSpan.From(frame, frameLength));
}
public void UseCase_123456789()
{
var buffer = Encoding.UTF8.GetBytes("123456789");
var crc = FeigChecksum.Calculate(BufferSpan.From(buffer));
Check.That(crc).IsEqualTo(0x6F91);
}
public void UseCase()
{
var buffer = new Byte[] {
0x0D,
0x00,
0x65,
0x00,
0x03,
0x03,
0x00,
0x44,
0x53,
0x0D,
0x30,
};
var crc = FeigChecksum.Calculate(BufferSpan.From(buffer));
Check.That(crc).IsEqualTo(0x0933);
}