public static ushort TestCrc(string data, int test)
{
var combinedBitArray = NRF24Helpers.GetBitArrayFromHexString(data);
ushort testCrc = 0xFFFF;
for (var offsetFront = 0; offsetFront <= combinedBitArray.Length; offsetFront++)
{
for (var i = combinedBitArray.Length - offsetFront; i >= 0; i--)
{
//backwards stripping
var subBitArray = NRF24Helpers.GetPartOfBitArray(combinedBitArray, offsetFront, i);
testCrc = NRF24Helpers.GetCrc16(subBitArray);
if (testCrc == 0xB4CC && test == 1)
{
var b = "a";
}
if (testCrc == 0x52F7 && test == 2)
{
var b = "a";
}
if (testCrc == 0x354E && test == 3)
{
var b = "a";
}
}
}
return(testCrc);
}
private NRF24Data CreateNRF24Data(NRF24Structure nrf24Structure)
{
if (nrf24Structure.NRF24Header == null || nrf24Structure.Data.Length < 5)
{
return(null);
}
// Set the NRF24 data part
var nrf24Data = new NRF24Data
{
NodeAddress = $"{nrf24Structure.NRF24Header.Address}{nrf24Structure.Data.Substring(0, 2)}"
};
var controlFieldString = nrf24Structure.Data.Substring(2, 4);
var controlFieldBitArray = NRF24Helpers.GetBitArrayFromHexString(controlFieldString);
nrf24Data.PayloadLength = NRF24Helpers.GetPartOfBitArray(controlFieldBitArray, 0, 6);
nrf24Data.Pid = NRF24Helpers.GetPartOfBitArray(controlFieldBitArray, 6, 2);
nrf24Data.NoAck = controlFieldBitArray[9];
nrf24Data.Payload = nrf24Structure.Data.Substring(4, nrf24Structure.Data.Length - 4);
var payloadFieldBitArray = NRF24Helpers.GetBitArrayFromHexString(nrf24Data.Payload);
// For last byte only the MSbit has value; rest will be cleared
payloadFieldBitArray = NRF24Helpers.GetPartOfBitArray(payloadFieldBitArray, 0, payloadFieldBitArray.Length - 7);
// Get the packet crc (the crc is located in last two bytes of the packet)
var crcOffset = payloadFieldBitArray.Length - 16;
nrf24Data.PacketCrc = NRF24Helpers.GetPartOfBitArray(payloadFieldBitArray, crcOffset, 16);
// Remove the crc bits from the bitarray before it is processed further
nrf24Data.PayloadBitArray = NRF24Helpers.GetPartOfBitArray(payloadFieldBitArray, 0, payloadFieldBitArray.Length - 16);
//TODO what about the string payload??
// ****
// Calculate the crc ourselfs
// Get the payload in bits, as the bitArray is already stripped of all unneeded stuff, the length is the amount of bits
//var payloadLengthBits = payloadFieldBitArray.Length;
//var packetLengthBits = 40 + 9 + payloadLengthBits;
// As the crc is calculated over the address, packet control field and payload, attach the two fields
//var combinedString = $"{this.NRF24Header.Address}{this.Data}";
//var combinedString = $"{this.Data}";
// Create the NRF24Mysensor part
nrf24Data.NRF24Mysensor = CreateNRF24Mysensor(nrf24Data);
return(nrf24Data);
}