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[Solved] How to send control command to POS printer?



  • Hi,

    I am creating an application which prints text through a POS printer.

    @#include "lanprinterui.h"
    #include "ui_lanprinterui.h"

    LanPrinterUI::LanPrinterUI(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::LanPrinterUI)
    {
    ui->setupUi(this);

    m_TextInput = ui->textEdit;
    m_pSocket   = new QTcpSocket();
    m_pSocket->connectToHost("192.168.1.20", 9100);
    m_ConnectStatus = true;
    
    QObject::connect(ui->pushButton, SIGNAL(clicked()), this, SLOT(print()));
    

    }

    LanPrinterUI::~LanPrinterUI()
    {
    delete ui;
    delete m_pSocket;
    }

    void LanPrinterUI::print()
    {
    const int Timeout = 5 * 1000;

    if (!m_ConnectStatus)
    {
        m_pSocket->connectToHost("192.168.1.20", 9100);
    }
    
    if (!m_pSocket->waitForConnected(Timeout))
    {
        //sent error
        qDebug ("error in waitForConnected()");
        qDebug (qPrintable(m_pSocket->errorString()));
        m_ConnectStatus = false;
        return;
    }
    
    m_ConnectStatus = true;
    QByteArray block;
    QDataStream out(&block, QIODevice::WriteOnly);
    out.setVersion(QDataStream::Qt_4_0);
    out << m_TextInput->toPlainText();
    out << '\n';
    m_pSocket->write(block);
    

    }
    @

    The prints works fine. But for POS printer there are control commands to do certain functions like : paper cut, cashdraw open etc.. For eg:

    Function: Partial cut
    Code:
    ASCII-------> ESC i
    Hex --------> 1B 69
    Decimal-----> 27 105

    When I try to send command 27 105 it just prints on paper.. I'm not exactly sure how to send it... Can someone suggest how to write to the socket...



  • I got the solution from a different forum..

    out << "\n\x1Bi";

    Hope this would help someone else...



  • @Abin hello albin ..can you please send me this full code...because im facing problem with printing using pos printer



  • @najeeb I second this. It would be great to download some source files of POS printing.


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