Send signal to serial port

Hi, I have a trouble.
I need to send a signal to serial port to pilot a relè.
I can't find how to send a Vcc signal for some second on a pin in java.
Someone have an idea?
Thanks a lot!
Edited by: Alberto.Marcigaglia on Aug 29, 2008 2:27 AM

There are many results from the search below:
http://www.google.com/search?q=java+serial+port
I suggest that you use the 3-rd party RXTX package rather than the obsolete javax.comm package. There are a number of very detailled posts in these Sun forums regarding the installation and use of RXTX - search for them.

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Melbourne, Australia
[email protected]

You should read replies to your posts more carefully since Craig Graham have
pointed out that VI to use to assert RTS and DTR lines of a serial port. You
also should search this group for the RS485 and RTS/DTR topic; it is a
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Jean-Pierre Drolet
"Slade Squire" a �crit dans le message de news:
[email protected]...
> Something else I forgot to mention....
>
> When I try and set RTS in the flow control parameter of Serial Port
Init.vi,
> it doesn't do anything!
> Why?
> (I know it doesn't do anything, because I have an oscilliscope set up on
the
> end of the com cable, wired to the RTS pin)
>
> "Slade Squire" wrote in message
> news:[email protected]...
> > I've posted a few times, about asserting the DTR signal line for the
> serial
> > ports.
> > To start off with, i have now come to the realization that I was
STUPIDLY
> > trying to set the wrong thing... I needed to set the RTS, not the
DTR!!!
> >
> > Most of the replies I got said to use the IN PORT and OUT PORT vi's,
from
> > the advanced, memory/portI/O palette.
> >
> > When i had a fiddle around with these, and looked them up in more depth,
I
> > found a few things...
> >
> > 1. I have read a few times, that these are not portable, because of
> machine
> > dependancy... Can anyone tell me how portable they are? Such as, are
they
> > fine for all Intel based architechure's, or what
> >
> > 2. I found that if I initialize the serial port, using the Serial Port
> > Init.vi, and then use the Out Port.vi, to set the RTS, by addressing the
> > register at 0x2FC, for COM 2, the next thing I did, which was write to
the
> > serial port, hung. When I highlighted execution, it was stuck in the
> Serial
> > Write.vi Can anybody tell me what I'm doing wrong?
> >
> > Your help would be greatly appreciated!
> >
> > --
> > Slade Squire
> > Programmer
> > Rectifier Technologies Pacific
> > Melbourne, Australia
> > [email protected]
> >
> >
> >
>
>
LabVIEW, C'est LabVIEW

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Message Edited by Dennis Knutson on 01-22-2010 01:42 PM
Attachments:
Parse String.png ‏16 KB

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Send signal to serial port

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