public XBeeInterfaceReceiver(Radio_Series1 p)
{
state = (int)RXState.IDLE;
buffer = new byte[128];
packet = new XBeeRXPacket();
parent = p;
}
public Boolean Fill(byte[] bytes, int len)
{
byte b;
int i;
for (i = 0; i < len; i++)
{
b = bytes[i];
switch (state)
{
case RXState.IDLE:
if (b == 0x7E)
{
bytesRead = 0;
state = RXState.LEN;
}
break;
case RXState.LEN:
if (bytesRead == 0)
{
packet.length = (uint)b << 8;
}
else if (bytesRead == 1)
{
packet.length |= b;
}
bytesRead++;
if (bytesRead == 2)
{
bytesRead = 0;
state = RXState.COMMAND;
}
break;
case RXState.COMMAND:
if (b == (byte)XBeeCommands.RX64)
{
packet.command = b;
packet.data = new byte[packet.length - 11];
packet.src64 = 0;
state = RXState.SRC64;
}
else if (b == (byte)XBeeCommands.TX)
{
bytesRead = 0;
state = RXState.UNKNOWN;
}
else
{
bytesRead = 0;
Debug.Print("UNKNOWN PACKET!! " + b);
state = RXState.UNKNOWN;
}
break;
case RXState.SRC64:
//Read 64bit Sender's Address
packet.src64Bytes[bytesRead] = b;
packet.src64 += (UInt64)b << (8 * bytesRead);
bytesRead++;
if (bytesRead == 8)
{
bytesRead = 0;
state = RXState.RSSI;
//get first interface packet and store 64bit address
if (parent.interfaceAddress == 0)
{
parent.interfaceAddress = packet.src64;
parent.interfaceAddressBytes = packet.src64Bytes;
//parent.telemetryThread.Start();
}
else
{
//ignore interface packets from the wrong address
if (parent.interfaceAddress != packet.src64)
{
//state = (int)RXState.UNKNOWN;
}
}
}
break;
case RXState.SRC16:
//Read 16bit Sender's Address
packet.src16 = (ushort)((packet.src16 << 8) | b);
bytesRead++;
if (bytesRead == 2)
{
bytesRead = 0;
state = RXState.RSSI;
}
break;
case RXState.RSSI:
packet.rssi = b;
state = RXState.OPTIONS;
break;
case RXState.OPTIONS:
packet.options = b;
state = RXState.DATA;
break;
case RXState.DATA:
//The beef
packet.data[bytesRead] = b;
bytesRead++;
if (bytesRead == packet.data.Length)
{
state = RXState.CHECKSUM;
}
break;
case RXState.CHECKSUM:
fullPacket = true;
state = RXState.IDLE;
break;
case RXState.UNKNOWN:
//ignore all bytes in packet before trying to parse again (all XBee API functions generate a confirmation packet sent as a packet)
//We dont care about most of them.
//We can get information about the current XBee module (like requesting its serial number or coordinator or network status)
bytesRead++;
if (bytesRead == packet.length)
{
state = RXState.IDLE;
bytesRead = 0;
}
break;
}
}
if (fullPacket) return true;
return false;
}
private RXState state; /** Current state of the receiver. */
#endregion Fields
#region Constructors
/** Constructor for the XBeeInterfaceReceiver class.
* @param p The parent Radio instance we're parsing packets for. */
public XBeeInterfaceReceiver(Radio p)
{
state = (int)RXState.IDLE;
packet = new XBeeRXPacket();
parent = p;
}
