C# multi-threading in RFID readers

Question

I've written a program which could connect to several RFID Reader and start to detect tags simultaneously. But because all of them are working on UI-Thread (Main Thread) my both UI and reading function become slower every time I add a new reader... I need to create a new thread for each reader and let that reader works with the new worker thread. But I don't know where have I import the new Thread() function in my c# program. I have a windows form timer for reading tags. I just changed my program to create a bgWorker for each reader. I removed my timer. I use a while loop for reading. but still every time I add a new reader and it starts to read tags despite it is working with a new working thread ID but the reading functionality of other readers become slower

public partial class frmMain : Form
{
    public frmMain()
    {
        InitializeComponent();
    }

    private void frmMain_Load(object sender, EventArgs e)
    {
        int count = 9;

        for (int i = 0; i < count; i++)
        {
            RfControl rfc = new RfControl();
            rfc.gTitle.Text = "Device" + Convert.ToString((i + 1));
            
            this.flowLayoutPanel1.Controls.Add(rfc);
        }
    }

    private void frmMain_FormClosing(object sender, FormClosingEventArgs e)
    {
        for(int i=0; i<this.flowLayoutPanel1.Controls.Count; i++)
        {
            RfControl rfc = (RfControl)this.flowLayoutPanel1.Controls[i];
        }
    }
}
 public partial class RfControl : UserControl
{
    RfReader rf = new RfReader();
    public RfControl()
    {
        InitializeComponent();
    }

    private void btnOpen_Click(object sender, EventArgs e)
    {
        try
        {
            rf.type = this.cbType.Text;
            rf.IPAddr = this.txtIP.Text.Trim();
            rf.port = Convert.ToInt32(this.txtPort.Text.Trim());
            rf.OnScan += new EventHandler(rf_OnScan);
            rf.Open();
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
    }

    void rf_OnScan(object sender, EventArgs e)
    {
        try
        {
            string value = ((RfReader)sender).value;
            if (this.lstContent.Items.IndexOf(value) == -1)
            {
                this.lstContent.Items.Add(value);
            }
            this.txtCount.Text = this.lstContent.Items.Count.ToString();
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
    }

    private void btnClose_Click(object sender, EventArgs e)
    {
        try
        {
            rf.Close();
        }
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
    }

    private void btnClear_Click(object sender, EventArgs e)
    {
        this.lstContent.Items.Clear();
        this.txtCount.Text = "0";
    }

    private void btnQuery_Click(object sender, EventArgs e)
    {
        rf.bgWorker.RunWorkerAsync();
    }
}

class RfReader
{
    Api api = new Api();
    ArrayList idList = new ArrayList();
    byte[,] tagData = null;
    byte v1 = 0;
    byte v2 = 0;
    int status = 0;
    int iMembankMask = 0, iStartAddr_Reserve = 0, iStartAddr_EPC, iStartAddr_TID, iStartAddr_User, reserveLen, epcLen, tidLen, userLen, readCnt, wordLen = 0;
    public int frmcomportindex;
    public byte readerAddr = 0xff;
    private byte fComAdr = 0xff;
    public int port = -1, openresult = 0;
    public string IPAddr = "";
    public string type = "";
    public string value = "";
    public string X = "";
    public string Y = "";
    public string Name = "";
    public System.Windows.Forms.Timer timer = null;
    public BackgroundWorker bgWorker = null;
    public RfReader()
    {
        bgWorker = new BackgroundWorker();
        bgWorker.DoWork += new DoWorkEventHandler(timer_Tick);
    }
    void timer_Tick(object sender, EventArgs e)
    {
        while (true)
        {
            Reader();
        }
    }
    public void Open()
    {
        if (type == "AR")
        {
            if (!api.isNetWorkConnect(IPAddr))
            {
                api.TcpCloseConnect();
                throw new Exception(IPAddr + " Open failed");
            }
            status = api.TcpConnectReader(IPAddr, Convert.ToInt32(port));
            if (status != ReaderApi.Api.SUCCESS_RETURN)
            {
                api.TcpCloseConnect();
                throw new Exception(IPAddr + " Open failed");
            }
            status = api.GetFirmwareVersion(255, ref v1, ref v2);
            if (status != ReaderApi.Api.SUCCESS_RETURN)
            {
                api.TcpCloseConnect();
                throw new Exception(IPAddr + " Open failed");
            }
            iStartAddr_Reserve = iStartAddr_EPC = iStartAddr_TID = iStartAddr_User = reserveLen = epcLen = tidLen = userLen = readCnt = 0;
            iMembankMask = 0;
            wordLen = 6;
            iMembankMask += 1;
            wordLen += 4;
            iStartAddr_Reserve = 0;
            reserveLen = 4;
            iMembankMask += 2;
            wordLen += 8;
            iStartAddr_EPC = 0;
            epcLen = 8;
            iMembankMask += 4;
            wordLen += 12;
            iStartAddr_TID = 0;
            tidLen = 12;
            iMembankMask += 8;
            wordLen += 10;
            iStartAddr_User = 0;
            userLen = 10;
            tagData = new byte[500, wordLen * 4];
            idList.Clear();
            throw new Exception(IPAddr + " Open Success");
        }
        else if (type == "ZK")
        {
            byte readerAddr = Convert.ToByte("FF", 16); // $FF;
            openresult = StaticClassReaderB.OpenNetPort(port, IPAddr, ref fComAdr, ref frmcomportindex);
            if ((openresult == 0x35) || (openresult == 0x30))
            {
                StaticClassReaderB.CloseNetPort(frmcomportindex);
                throw new Exception(IPAddr + " Open failed");
            }
            if (openresult == 0)
            {
                throw new Exception(IPAddr + " Open Success");
            }
        }
    }
    public void Close()
    {
        if (type == "AR")
        {
            api.TcpCloseConnect();
        }
        else if (type == "ZK")
        {
            StaticClassReaderB.CloseNetPort(frmcomportindex);
            frmcomportindex = -1;
        }
    }
    public event EventHandler OnScan;
    public void Reader()
    {
        if (type == "AR")
        {
            readCnt = 0;
            int getCount = 0;
            string strTemp = "", strAnteNo = "", strEPC = "", strSubEPC = "", strTID = "", strReserve = "", strUser = "";
            status = api.Gen2MultiTagRead(255, (byte)iMembankMask, (byte)iStartAddr_Reserve, (byte)reserveLen, (byte)iStartAddr_EPC, (byte)epcLen, (byte)iStartAddr_TID, (byte)tidLen, (byte)iStartAddr_User, (byte)userLen, ref readCnt);

            if (status == Api.SUCCESS_RETURN)
            {
                if (readCnt > 0)
                {
                    if (api.GetTagData(255, ref tagData, readCnt, ref getCount) == Api.SUCCESS_RETURN && getCount > 0)
                    {
                        for (int loop = 0; loop < getCount; loop++)
                        {
                            strTemp = "";
                            for (int j = 1; j <= (int)tagData[loop, 0]; j++)
                                strTemp += string.Format("{0:X2}", tagData[loop, j]);
                            strEPC = strTemp.Substring(2, 24);
                            strReserve = strTemp.Substring(26, reserveLen * 4);
                            strSubEPC = strTemp.Substring(26 + reserveLen * 4, epcLen * 4);
                            value = strTemp.Substring((26 + reserveLen * 4 + epcLen * 4) + 8, 16);
                            strUser = strTemp.Substring(26 + reserveLen * 4 + epcLen * 4 + tidLen * 4, userLen * 4);
                            //OnScan(this, new EventArgs());
                        }
                    }
                }
                
            }
        }
        else if (type == "ZK")
        {
            
            int CardNum = 0, Totallen = 0, EPClen, m, CardIndex;
            byte[] EPC = new byte[5000];
            string temps, s;
            byte AdrTID = 0, LenTID = 0, TIDFlag = 0;
            AdrTID = 2;
            LenTID = 4;
            TIDFlag = 1;
            byte Qvalue = 4;
            byte Session = 0;
            string lastEPC = "";
            int fCmdRet = StaticClassReaderB.Inventory_G2(ref fComAdr, Qvalue, Session, AdrTID, LenTID, TIDFlag, EPC, ref Totallen, ref CardNum, frmcomportindex);

            if ((fCmdRet == 1) | (fCmdRet == 2) | (fCmdRet == 3) | (fCmdRet == 4) | (fCmdRet == 0xFB))//The search is over
            {
                if (CardNum == 0)
                {
                    return;
                }
                byte[] daw = new byte[Totallen];
                Array.Copy(EPC, daw, Totallen);
                temps = ByteArrayToHexString(daw);
                
                if (temps == "") return;
                m = 0;
                for (CardIndex = 0; CardIndex < CardNum; CardIndex++)
                {
                    EPClen = daw[m];
                    string TID = temps.Substring(m * 2 + 2, EPClen * 2);
                    lastEPC = TID;
                    m = m + EPClen + 2;
                    value = TID;
                }
            }
        }
    }
    
}

Answer 1

Use Thread-Class instead of BgWorker and Invoke all UI-Access. Do the Invoke only when you access UI-Elements, do NOT invoke if you do rfid-reader operations. Do never use timers for this kind of work as you already unterstood. If you need more help, just contact me on contact form