public ProtocolReadState protocol_read_byte(byte data)
{
switch (state)
{
case ProtocolReadState.IDLE:
if (data == START_BYTE)
{
// start reading
buffer_ptr = 0;
buffer[0] = data;
state = ProtocolReadState.EXPECTING_ID;
}
break;
case ProtocolReadState.EXPECTING_ID:
buffer[++buffer_ptr] = data;
state = ProtocolReadState.EXPECTING_LENGTH;
break;
case ProtocolReadState.EXPECTING_LENGTH:
buffer[++buffer_ptr] = data;
state = (data > 0) ? ProtocolReadState.READING_DATA : ProtocolReadState.EXPECTING_END;
break;
case ProtocolReadState.READING_DATA:
{
// read in byte into buffer
buffer[++buffer_ptr] = data;
byte data_length = buffer[2];
if (buffer_ptr == data_length + 2)
{
state = ProtocolReadState.EXPECTING_END;
}
}
break;
case ProtocolReadState.EXPECTING_END:
if (data == END_BYTE)
{
buffer[++buffer_ptr] = data; // unnecessary but w/e
state = ProtocolReadState.PACKET_COMPLETE;
}
else
{
state = ProtocolReadState.IDLE; // throw away packet
}
break;
case ProtocolReadState.PACKET_COMPLETE:
break;
default:
break;
}
return(state);
}
public bool protocol_packet_ready(out KeypadSerialPacket packet)
{
packet = new KeypadSerialPacket();
if (state == ProtocolReadState.PACKET_COMPLETE)
{
packet.id = buffer[1];
packet.length = buffer[2];
packet.data = new byte[packet.length];
Buffer.BlockCopy(buffer, 3, packet.data, 0, (int)packet.length);
state = ProtocolReadState.IDLE;
return(true);
}
return(false);
}