Signal detection on pins of parallel port

hello,
i am using the outport.vi in order to write to the parallel port of my windows 98 pc. I am writing a value to the port register. To detect that, i am trying to detect a signal change directly on the pin of the parallel port using an oscilloscope. I don´t detect anyhting although the vi ran without complaining. What am i doing wrong ?
saludos
miriam

Hi miriam,
I never used the access to parallel port from LV but from C based programs. As I know outport should do under Win 98.
Are you aware that the port nubmer is in Hex? The address can change if you have one or two parallel ports in your machine.
If you have one port it is 0x378 for LPT1.
If you have two ports it is 0x278 for LPT1 and 0x378 for LPT2.
Waldemar
Waldemar
Using 7.1.1, 8.5.1, 8.6.1, 2009 on XP and RT
Don't forget to give Kudos to good answers and/or questions

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Setting Pins on Parallel Ports

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You must to forces the buffered output bytes to be written out to the underlying output stream.
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I am trying to acquire pulse signal (TTL 0 ,+5v) using parallel port (SPP 25 pins) on pin 12.

The state register adress is 379h. When I run continuously this VI, the value diplays 78 and 58 periodycally.
I think that 0 correponds to 58 and +5v correponds 78. Is this correct ?
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I attached the I am using.
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Hi
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Is it possible to get direct access to parallel port pins under Windows NT? What can I do

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Signal detection on pins of parallel port

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