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serial port in VB

Posted: 24. Mar 2009, 16:05
by ircoms
Goodafternoun:

so, I use linux redhat over vitualbox 2.4.1 over window xp pack 3, so i have the problem of communication via serial port (ttyS0), i cheked my ttyS0 configuration (linux) it seems like COM1 configuatuion(win) i dont undersrand what is the problem i can't change corret data please help me
cordialy

Re: serial port in VB

Posted: 24. Mar 2009, 16:10
by ircoms
Hi;
my question is :
is there problem with asynchronous communication in VB because I cant exchange correct data with other linux station cordialy

Re: serial port in VB

Posted: 2. Apr 2009, 02:25
by Zebulon
Hi..

just like in real live - if you can't / or don't - speak the expected language you won't get a (correct) reply! :mrgreen:

Regards,
Zebulon

Re: serial port in VB

Posted: 2. Apr 2009, 02:49
by Perryg
ircoms wrote:Hi;
my question is :
is there problem with asynchronous communication in VB because I cant exchange correct data with other linux station cordialy
Have you turned on the serial port in the VBox GUI?
Have a look at section 3.7.6 of the users manual. It pretty much explains it all.

Re: serial port in VB

Posted: 2. Apr 2009, 09:19
by ircoms
yes i Have turned on the serial port in the VBox, I can exchange DATA via the port but not correte

Re: serial port in VB

Posted: 2. Apr 2009, 09:22
by ircoms
My problem is I can't exhange correct data between 2 linux pc (one over VB over window)via Serial port i hope that you can undertand me
thanx in advance

Re: serial port in VB

Posted: 2. Apr 2009, 11:53
by vbox4me2
What exactly is going wrong? are you using proper hw/sw handshaking?

Re: serial port in VB

Posted: 2. Apr 2009, 12:05
by ircoms
when i try to send file.txt i receve the file in diffrent format for exemple i send
<I'm in linux over VB over windows>
file.txt

"The HylaFAX configuration parameter JobControlCmd specifies the script that is used to apply per-job controls on job characteristics such as the time-of-day to place a call.
The controls program is passed the respective job ID number as the first and only argument.

The controls program should produce a simple line-based ASCII output containing a series of records of the form: "


i reseve <linux>
file.txt
"the h<<u_<àçi_ulùmùmfiguratiojbnb jjks452222222xnbkzkhhjdjhkjkjs......."
i checked it withow VB (lwindows to linux ) it was well i received the good file
thank you

Re: serial port in VB

Posted: 2. Apr 2009, 12:48
by vbox4me2
Speed and/or handshake problem, play with the speed and verify handshake is working.

Re: serial port in VB

Posted: 2. Apr 2009, 13:50
by ircoms
i cheked the speed the parity .... no problem, i think VB don't manage well asyncrous communication as virtal pc

Re: serial port in VB

Posted: 2. Apr 2009, 13:53
by ircoms
thank you very much sir i continue searching

Re: serial port in VB

Posted: 5. Apr 2009, 02:03
by TKreuzer
I am experiencing similar problems. And I spoke to other people with different configurations and similar problems.

I am using:
- Windows XP host
- VBox 2.1.4
- Virtual serial port: COM1, irq4, 0x3f8, host-pipe, [x]Create pipe

Now I boot up ReactOS, which sends serial debugging information as plain text on COM1.
I can attach a terminal to the created pipe and receive data.
As soon as larger amounts of data are sent quickly, stuff starts to get weird and parts of the data disappear (characters missing).
The described method works flawlessly on qemu and VMWare and with a serial terminal also with real Hw.

I replaced my named pipe terminal with IO Ninja. The results were better, but still characters were missing. Same using putty and connecting directly to the pipe, it was even better but still characters were missing as soon as a lot of text was sent.

Wild guess: the virtual serial port doesn't properly set Line Status Register's Empty Transmitter Holding Register
and the sender puts byte after byte into the virtual UART buffer, not noticing when it's full.

Edit: using a smaller BAUD rate on the guest improves the situation, but even at 9600 BAUD it's not perfect.

Re: serial port in VB

Posted: 5. Apr 2009, 12:31
by vbox4me2
Have a look in bugtracker, if its not there please report a bug report on Bugtracker with all the details.

Re: serial port in VB

Posted: 5. Apr 2009, 23:53
by TKreuzer