Example for bikr

class rfidDevice extends InputPort
{
    serPort = null;
    enabled = true;
    rxData = "";

    constructor(port)
    {
        serPort = port;
        serPort.configure(115200,8, PARITY_NONE,1,NO_CTSRTS);
        enable();
    }

    function enable()
    {
        rxData = "";
        enabled = true;
        poll();
    }

    function disable()
    {
        enabled = false;
    }

    // Receive 0 = disable, 1 = enable on our input port
    function set(value)
    {
        if(value == 0)
        {
            disable();
        }
        else
        {
            enable();
        }
    }

    function poll()
    {
        if(enabled)
        {
            imp.wakeup(0.1, poll.bindenv(this));

            serPort.write(0x10);
            serPort.write(0x03);
            serPort.write(0x00);

            local byte = serPort.read();

            while(byte != -1)
            {
                //server.log(format("Raw: %02x", byte));
                switch(byte)
                {
                    case 0xFF : // Start of data
                        //server.log("Caught Initial Byte");
                        rxData = "";
                        break;

                    default:    // ID byte
                        rxData += byte;

                        // Add some code here to decide when the received data is complete
                        // and perhaps send it to an output?  e.g.
                        if(strlen(rxData) == 8)
                        {
                            output.set(rxData);
                            server.log(format("Got ID: %s", rxData));
                            rxData = "";
                        }
                        break;
                }

                // Get the next byte
                byte = serPort.read();
            }
        }
    }
}

local output = OutputPort("Result", "string");
local rfid = rfidDevice(hardware.uart1289);

imp.configure("Sticker Reader",[rfid], [output]);

server.log("Starting Scan");

// End of code.