Receiving data via serial connection C#

Question

I need to do a program that has to send a command to a radio connected via serial port and this returns your ID. The connection to the port and the sending of data is ok, when I send something the light flashes. But I need your return and from what I saw in debug the program does not enter the serial classPort1_DataReceived. What could be?

Follows the code:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO.Ports;  // necessário para ter acesso as portas     


namespace serialteste
{
public partial class Form1 : Form
{
    string RxString;

    public Form1()
    {
        InitializeComponent();

    }


    private void atualizaListaCOMs()
    {
        int i;
        bool quantDiferente;    //flag para sinalizar que a quantidade de portas mudou

        i = 0;
        quantDiferente = false;

        //se a quantidade de portas mudou
        if (comboBox1.Items.Count == SerialPort.GetPortNames().Length)
        {
            foreach (string s in SerialPort.GetPortNames())
            {
                if (comboBox1.Items[i++].Equals(s) == false)
                {
                    quantDiferente = true;
                }
            }
        }
        else
        {
            quantDiferente = true;
        }

        //Se não foi detectado diferença
        if (quantDiferente == false)
        {
            return;                     //retorna
        }

        //limpa comboBox
        comboBox1.Items.Clear();

        //adiciona todas as COM diponíveis na lista
        foreach (string s in SerialPort.GetPortNames())
        {
            comboBox1.Items.Add(s);
        }
        //seleciona a primeira posição da lista
        comboBox1.SelectedIndex = 0;
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        //atualizaListaCOMs();

    }





    private void btConectar_Click(object sender, EventArgs e)
    {
        if (serialPort1.IsOpen == false)
        {
            try
            {


                serialPort1.PortName = comboBox1.Items[comboBox1.SelectedIndex].ToString();
                serialPort1.Open();

            }
            catch
            {
                return;

            }
            if (serialPort1.IsOpen)
            {
                btConectar.Text = "Desconectar";
                comboBox1.Enabled = false;

            }
        }
        else
        {

            try
            {
                serialPort1.Close();
                comboBox1.Enabled = true;
                btConectar.Text = "Conectar";
            }
            catch
            {
                return;
            }

        }
    }

    private void Form1_FormClosed(object sender, FormClosedEventArgs e)
    {
        if (serialPort1.IsOpen == true)  // se porta aberta
            serialPort1.Close();            //fecha a porta


    }

    private void btEnviar_Click(object sender, EventArgs e)
    {
        if (serialPort1.IsOpen == true)          //porta está aberta
            serialPort1.Write(textBoxEnviar.Text);  //envia o texto presente no textbox
    }

    private void trataDadoRecebido(object sender, EventArgs e)
    {
        textBoxReceber.AppendText(RxString);
    }

    private void serialPort1_DataReceived(object sender, SerialDataReceivedEventArgs e)
    {


        textBoxReceber.Text="alguma coisa recebeu";
        RxString = serialPort1.ReadExisting();              //le o dado disponível na serial
        this.Invoke(new EventHandler(trataDadoRecebido));   //chama outra thread para escrever o dado no text box
    }

    private void Atualizar_Click(object sender, EventArgs e)
    {
        atualizaListaCOMs();
    }      


}
}

Answer 1

To trigger the process would be:

_serialPort.DataReceived += new SerialDataReceivedEventHandler(RecebeDadosSerial); 

However, it would be interesting to send us a manual about your device. You may not be sending anything to your serial. It may be that you need to send the ENQ command to get back, it can be done as follows:

string ENQ = "\u0005\r\n"; // -> \n padrão de Escape 
        _serialPort.Write(ENQ);