Sending Multiple Strings over TCP

[GCE_]

Hi guys!
I am working on a measurement module, which is controlled via TCP commands.
First I need to initialize 4 ports as output and after that I need to set the ports to either high or low (0 or 1).
My Problem is, that the first 2 commands are recognized by the module and the other two commands not and I don't know why.
I tried everything and still do not have any solution for it. I hope you guys can help me.
Here is my source:

#include "tcpsocket.h"

tcpsocket::tcpsocket(QObject *parent) : QObject(parent)
{
    socket = new QTcpSocket(this);
    IpMoonCard="192.168.0.153";
    connect(socket, &QTcpSocket::connected,this, &tcpsocket::connected);
    connect(socket, &QTcpSocket::disconnected, this, &tcpsocket::disconnected);
    connect(socket, &QTcpSocket::readyRead, this, &tcpsocket::readyRead);
    connect(socket,&QTcpSocket::bytesWritten, this, &tcpsocket::bytesWritten);
}

void tcpsocket::connectSocket()
{
    socket->connectToHost(IpMoonCard,33330);
    initPorts();
}

void tcpsocket::writeMoonCard()
{
    /*if(q<=15){
        q+=1;
    }
    else {
        q=0;
    }*/
    /*value= QString("%1").arg(q,4,2,QChar('0'));
    socket->write(("PORT:SET:IO29:"+value[0]).toUtf8());
    QThread::msleep(100);
    socket->write(("PORT:SET:IO4:"+value[1]).toUtf8());
    QThread::msleep(100);
    socket->write(("PORT:SET:IO41:"+value[2]).toUtf8());
    QThread::msleep(100);*/
    socket->write("PORT:SET:42:1");
    socket->write("PORT:SET:41:1");
    socket->write("PORT:SET:04:1");
    socket->write("PORT:SET:29:1");
}

void tcpsocket::initPorts()
{
    socket->write("PORT:DIR:42:output");
    socket->write("PORT:DIR:41:output");
    socket->write("PORT:DIR:04:output");
    socket->write("PORT:DIR:29:output");
    writeMoonCard();
}

void tcpsocket::connected()
{
    qDebug()<<"Socket connected";
}

void tcpsocket::disconnected()
{
    qDebug()<<"Socket disconnected";
}

void tcpsocket::readyRead()
{
    qDebug()<<"Bytes Avalable: "<<socket->bytesAvailable();

    if(socket->bytesAvailable()>0){
        recBuf+=socket->readAll();
        qDebug()<<"\n"<<recBuf<<"\n";
        return;
    }
    else {
        qDebug()<<recBuf;
        recBuf="";
        return;
    }

}

void tcpsocket::bytesWritten(qint64 bytes)
{
    qDebug()<<bytes<<" bytes written\n";
}

This is my source for main.cpp:

#include <QCoreApplication>
#include <bitset>
#include <QDebug>
#include <iostream>
#include "tcpsocket.h"
int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    tcpsocket socket;
    socket.connectSocket();
    return a.exec();
}

For your information: I am using QT 5.15, Windows10 Pro, Qt Creator 4.12.4

Thank you in advance!

[jsulm]

@GCE_ said in Sending Multiple Strings over TCP:

initPorts();

You should call it in connected() as connectToHost() takes some time.

[J.Hilk]

@GCE_
Additionally to what @jsulm said, give your os time operate the port/flush the data.

you're already listening to the bytesWritten signal. So instead of writing all commands directly one after an other, write one, and wait until bytesWritten-signal signals the correct amount if bytes written and then send the next command

[GCE_]

@J-Hilk said in Sending Multiple Strings over TCP:

@GCE_
Additionally to what @jsulm said, give your os time operate the port/flush the data.

you're already listening to the bytesWritten signal. So instead of writing all commands directly one after an other, write one, and wait until bytesWritten-signal signals the correct amount if bytes written and then send the next command

Ok I did what @jsulm said and moved my command.
So @J-Hilk you mean I should do this after every single command?

socket->write("PORT:SET:42:1");
    socket->waitForBytesWritten();

[J.Hilk]

@GCE_ said in Sending Multiple Strings over TCP:

So @J-Hilk you mean I should do this after every single command?
socket->write("PORT:SET:42:1");
socket->waitForBytesWritten();

NOUGH!

something like this:

QVector<QString> m_commands{"PORT:SET:42:1","PORT:SET:41:1","PORT:SET:04:1","PORT:SET:29:1"};
int commandIndex(0);


void tcpsocket::bytesWritten(qint64 bytes)
{
    qDebug()<<bytes<<" bytes written\n";
    m_bytesWrittenSofar + bytes;
    if(m_bytesWrittenSofar == m_commands.at(commandIndex).size()){
         if(++commandIndex < m_commands.size())
          socket->write( m_commands.at(commandIndex));
    }
}
....

Beware mockup code, will not compile, but you get the idea

[GCE_]

@J-Hilk Thank you very much, it worked!
You are awesome guys :D

another question:
when naming a variable, why it begins with m_ ?
Is it meant for membervariable?

[mrjj]

@GCE_
Hi
Yes m_ is used to indicate its a member of the class.

[GCE_]

Thank you guys! The problem is solved now!