static void Main()
{
CallField call1 = Ax25Frame.DecodeCallsign(StringToByteArray("9A 60 98 A8 8A 40 EA"));
CallField call2 = Ax25Frame.DecodeCallsign(StringToByteArray("9A 60 98 A8 8A 40 6A"));
//byte b = (byte)'M';
//BitArray ba = new BitArray(new[] { b });
//Console.WriteLine(ba.ToOnesAndZeroes());
//string frame = "C0 00 AA A2 A4 AC AA A2 60 9A 60 98 A8 8A 40 E0 AE 92 88 8A 62 40 62 AE 92 88 8A 64 40 65 03 F0 27 77 59 44 6C 20 1C 5B 2F 3E 0D C0";
string frame = "C0 00 AA A2 A4 AC AA A2 60 9A 60 98 A8 8A 40 EA AE 92 88 8A 62 40 62 AE 92 88 8A 64 40 65 03 F0 27 77 59 44 6C 20 1C 5B 2F 3E 0D C0";
// C0 00 AA A2 A4 AC AA A2 60 9A 60 98 A8 8A 40 EA AE 92 88 8A 62 40 62 AE 92 88 8A 64 40 65 03 F0 27 77 59 44 6C 20 1C 5B 2F 3E 0D C0
// C0 00 AA A2 A4 AC AA A2 60 9A 60 98 A8 8A 40 6A AE 92 88 8A 62 40 62 AE 92 88 8A 64 40 64 9A 60 98 A8 8A 40 73 03 F0 27 77 59 44 6C 20 1C 5B 2F 3E 0D C0
// M0LTE-5 ** **
// C0 00 AA A2 A4 AC AA A2 E0 9A 60 98 A8 8A 40 EA AE 92 88 8A 62 40 E2 AE 92 88 8A 64 40 E4 9A 60 98 A8 8A 40 F3 03 F0 27 77 59 44 6C 20 1C 5B 2F 3E 0D C0
byte[] frameBytes = StringToByteArray(frame);
Ax25Frame.TryParse(frameBytes, out Ax25Frame f);
byte[] kf = f.ToKissFrame();
string s2 = kf.ToHexString();
Ax25Frame.TryParse(StringToByteArray(s2), out Ax25Frame f2);
//Process(frameBytes);
Debugger.Break();
}
internal static CallField DecodeCallsign(byte[] addressField)
{
var result = new CallField();
var sb = new StringBuilder();
for (int i = 0; i < 6; i++)
{
char c = (char)(addressField[i] >> 1);
sb.Append(c);
}
string call = sb.ToString().Trim();
byte ssidByte = addressField[6];
// bits numbered from the right, per fig 3.5 of http://www.tapr.org/pdf/AX25.2.2.pdf
// bit 0 (rightmost) is the HDLC address extension bit, set to zero on all but the last octet in the address field, where it is set to one.
result.IsLast = ssidByte.GetBit(0);
// ssid is next, it's just a 4-bit number, 0-15
int ssid = GetSsid(ssidByte);
// reserved bits, set to 1 when not implemented
bool reserved1 = ssidByte.GetBit(5);
bool reserved2 = ssidByte.GetBit(6);
// command/response bit of an LA PA frame, see section 6.1.2 of http://www.tapr.org/pdf/AX25.2.2.pdf
result.CHBit = ssidByte.GetBit(7);
if (ssid == 0)
{
result.Call = call;
}
else
{
result.Call = String.Format("{0}-{1}", call, ssid);
}
return(result);
}
public static ParseResult TryParse(byte[] kissFrame, out Ax25Frame ax25Frame)
{
ax25Frame = null;
if (kissFrame[0] != 0xc0 || kissFrame[1] != 0x00)
{
return(new ParseResult {
FailReason = String.Format("Not a KISS frame, expected c0 00, got {0:X2} {1:X2}", kissFrame[0], kissFrame[1])
});
}
if (kissFrame.Last() != 0xc0)
{
return(new ParseResult {
FailReason = String.Format("Frame looks incomplete, expected c0 at end, got {0:X2}", kissFrame.Last())
});
}
ax25Frame = new Ax25Frame();
ax25Frame.Source = DecodeCallsign(getSourceBytes(kissFrame));
ax25Frame.Dest = DecodeCallsign(getDestBytes(kissFrame));
byte[][] digis = getDigis(kissFrame);
foreach (byte[] digiField in digis)
{
CallField call = DecodeCallsign(digiField);
Debug.WriteLine(call);
ax25Frame.Digis.Add(call);
}
ax25Frame.InfoBytes = getInfo(kissFrame);
ax25Frame.Info = Encoding.ASCII.GetString(ax25Frame.InfoBytes);
return(new ParseResult {
Result = true
});
}
static byte[] EncodeCallsign(CallField cf)
{
string callAndSsid = cf.Call;
var parts = (callAndSsid ?? "").Trim().Split('-');
if (parts.Length != 1 && parts.Length != 2)
{
throw new ArgumentException($"Invalid callsign {callAndSsid}");
}
if (string.IsNullOrWhiteSpace(parts[0]))
{
throw new ArgumentException($"Invalid callsign {parts[0]}");
}
int ssid;
if (parts.Length == 1)
{
ssid = 0;
}
else
{
ssid = int.Parse(parts[1]);
}
if (ssid < 0 || ssid > 15)
{
throw new ArgumentException($"Invalid SSID {ssid} in {callAndSsid}");
}
string call = parts[0].Trim();
while (call.Length < 6)
{
call += " ";
}
// callsign bytes
var result = new byte[7];
for (int i = 0; i < 6; i++)
{
result[i] = (byte)(call[i] << 1);
}
// ssid byte
// bits numbered from the right, per fig 3.5 of http://www.tapr.org/pdf/AX25.2.2.pdf
// bit 0 (rightmost) is the HDLC address extension bit, set to zero on all but the last octet in the address field, where it is set to one.
result[6] = result[6].SetBit(0, cf.IsLast);
// ssid is next, it's just a 4-bit number, 0-15
result[6] = SetSsid(result[6], ssid);
// reserved bits, set to 1 when not implemented
result[6] = result[6].SetBit(5, cf.Bit5Reserved);
result[6] = result[6].SetBit(6, cf.Bit6Reserved);
// command/response bit of an LA PA frame, see section 6.1.2 of http://www.tapr.org/pdf/AX25.2.2.pdf
result[6] = result[6].SetBit(7, cf.CHBit);
return(result);
}
