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Parallel Port Error

When trying to write to an instrument connected to LPT1using the serial port
com vi's, I get a device not found error. Any ideas?


Thx Steve
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Message 1 of 4
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SWYNHURST wrote:

> When trying to write to an instrument connected to LPT1using the serial port
> com vi's, I get a device not found error. Any ideas?
>
> Thx Steve

Make sure that you have the proper settings in the labview.ini file.
Each port should be listed and the serial VIs will use them in the
order listed. IE if com1 is listed first it is serial port 0.
Kevin Kent
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Pardon me if I'm being dense, but how can a serial VI work with a parallel port?
(LPT1 and COM1 are as different as ethernet and USB, for example.)

"Kevin B. Kent" wrote:

> SWYNHURST wrote:
>
> > When trying to write to an instrument connected to LPT1using the serial port
> > com vi's, I get a device not found error. Any ideas?
> >
> > Thx Steve
>
> Make sure that you have the proper settings in the labview.ini file.
> Each port should be listed and the serial VIs will use them in the
> order listed. IE if com1 is listed first it is serial port 0.
> Kevin Kent

--

Best Regards,
Mike T

Mike Tranchemontagne
Consulting Applications Engineer
603-598-4773 (Direct Line and Cell)

TeraComm, Inc.
148 Main Street
Building A, 3rd Floor
North Andove
r, MA 01845
877-900-TERA (8372)
978-557-9490 (FAX)
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Message 3 of 4
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Mike Tranchemontagne wrote:

> Pardon me if I'm being dense, but how can a serial VI work with a parallel port?
> (LPT1 and COM1 are as different as ethernet and USB, for example.)
>
> "Kevin B. Kent" wrote:
>
> > SWYNHURST wrote:
> >
> > > When trying to write to an instrument connected to LPT1using the serial port
> > > com vi's, I get a device not found error. Any ideas?
> > >
> > > Thx Steve
> >
> > Make sure that you have the proper settings in the labview.ini file.
> > Each port should be listed and the serial VIs will use them in the
> > order listed. IE if com1 is listed first it is serial port 0.
> > Kevin Kent
>
> --

Mike,
It does sound a bit strange but it is perfectly valid to use the parallel
port with the serial VIs. It is even
mentioned in the help files under
the serial I/O topic. It all boils down (eventually) to the fact that the
serial I/O VIs simply put values into a memory location. The hardware
(be it serial RS-232 port or parallel port) transforms the data into the
proper format and sends it out the connector.

There are differences in handshaking though so it is best (I believe)
to use SW handshaking when using the parallel port. (Someone correct me if wrong).

Kevin Kent
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