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No. 1314 Re: Re: Re: EZL-70(A) abort his work after sending 8192 bytes. 2015-01-07

Thank you for your detailed information.

This case seems to occur by buffer overflow of virtual COM port made by ezVSP.
I faced a similar problem with virtual COM port.
Here are solutions.
1. Enabling RTS/CTS flow control on the COM5.
2. Enabling [Emulation of Baudrate] option on the advanced menu of the virtual port setting.
(I recommend using the latest version of ezVSP - 4.1B)

You can avoid the data loss using at least one of solutions.

Best Regards,

> Joerg wrote:
> ------------------------------------
> Hi,
>
> my situation is the following: On "Windows 7 Professional", I use two terminal programms on both ends (com5 and com10).
> Com5 is a virtual com port created by your ezVSP software. Com10 is the EZL-70(A).
> I am using this code to produce the error:
>
> void MainWindow::writeBlock()
> {
> QByteArray data;
> unsigned char c;
> c = 'A';
>
> if (serial->isOpen()) {
> for (int i = 0; i < 59; i++ ) {
> data.append(c);
> c++;
> }
> data.append('> ');
> for (int i = 0; i < 1000; i++ ) {
> if (serial->write(data)<0) {
> QMessageBox::about(this,"Error" ,serial->errorString());
> }
> }
> }
> }
>
>
> The direction com10 to com5 works fine. Only the way from com5 (virtual com port) to com10 is wrong.
> Please open the screenshot. The ABC... at the 8193 char has overwritten the abc.. !
>
> After further investigation I have found the following:
>
> 1) With ezVSP 4.0 D the transmission stops after 8192 bytes.
> 2) With ezVSP 4.1 B the transmission will be modified as you can see in the screenshot.
> 3) With a 0-modem cable between com5 and com10 everything is fine. (Using the same USB to RS232 dongles and the same testsoftware ).
>
> Please try to reprodruce this with ezVSP 4.1B.
>
> Thanks in advance.
>
> Regards
> Joerg
>
>
> > Sollae Systems wrote:
> > ------------------------------------
> > Hi.
> >
> > Unfortunately, we could not find any data loss with the same condition of yours.
> > We tried to send 16,384 bytes data to both socket and serial sides at the same time.
> > Can you give us more specific information about your situation?
> >
> > Thanks in advance.
> >
> > > Joerg wrote:
> > > ------------------------------------
> > > Hello Support!
> > >
> > > We are using a EZL-70 (A) with the firmware version 1.2E, 9600 baud, 8E1, "Tx Delay" is on, "Disable TCP Transmission Delay" is on as a "TCP Server".
> > >
> > > Whenever I send more than 8192 characters stops the transmission.
> > > The rest of the data will be lost. In the most cases, I can continue
> > > by sending the message again.
> > >
> > > Is there a new firmware to solve the problem?
> > >
> > > Regards,
> > > Joerg
Writer Sollae Systems Company