Tests with ESP01 and AT commands

#1 · February 26, 2026, 10:44 am

I'm doing some tests with ESP01. I managed to zealize TCP connections with ESP01 client and I wanted to implement server mode.

I started a server with the following code:

void Esp01::StartServer(int port)
{
    m_server = new QTcpServer();
    bool no_err = QObject::connect(m_server, &QTcpServer::newConnection, [=](){ onNewConnection(); });
    if (no_err) qDebug() << "CONNECT RIUSCITO";

    if (m_server->listen(QHostAddress("127.0.0.1"), port)) {
        m_uartReply = m_OK;
        uartReply = true;
        if (m_debug) qDebug() << "ESP01 SERVER AT simulato - porta " << port;
    } else {
        if (m_debug) qDebug() << "Errore listen:" << m_server->errorString();
        m_uartReply = m_ERROR; uartReply = true;
    }
}

The server is created and listens on the chosen port (tested with "telnet 127.0.0.1 8080")

but the "connect" doesn't work:

QObject::connect(m_server, &QTcpServer::newConnection, [=](){ onNewConnection(); });

onNewConnection() it does not happen while:

    QObject::connect( tcpSocket, &QTcpSocket::connected   , [=](){ tcpConnected(id); });
    QObject::connect( tcpSocket, &QTcpSocket::disconnected, [=](){ tcpDisconnected(id); });
    QObject::connect( tcpSocket, &QTcpSocket::readyRead   , [=](){ tcpReadyRead(id); });

It works well, can you give me some advice?

Regards