out port.vi - usb - parallel

[rldvw]

I'm using a vi with an outport.vi in LabView 8.2 to control an electric motor. In my new laptop there is no parallel port so I tried to use a parallel-to-USB adapter. I lost communication between the laptop and the motor. How do I solve this problem?

Thanks

[Tim Norris]

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rldvw wrote:

I'm using a vi with an outport.vi in LabView 8.2 to control an electric motor. In my new laptop there is no parallel port so I tried to use a parallel-to-USB adapter. I lost communication between the laptop and the motor. How do I solve this problem?

Thanks

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What OS are you using? I had a similar problem when using USB-parallel adaptors: Under WindowsXP the adaptor appeared as a "Virtual Printer Port" and I was unable to communicate with it using outport.vi, under Windows2K everything worked OK.

[rolfk]

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rldvw wrote:

I'm using a vi with an outport.vi in LabView 8.2 to control an electric motor. In my new laptop there is no parallel port so I tried to use a parallel-to-USB adapter. I lost communication between the laptop and the motor. How do I solve this problem?

Thanks

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outport directly adresses IO registers. Most virtual port drivers don't support that as it is rather difficult, error prone and in most cases won't work as expected anyhow due to timing problems and such.

Unless you can change your software to use VISA to access the parallel port, which goes through the Windows COMM API for which such USB adapters have a virtual driver normally, you are quite likely in deep trouble. Basically outport was a nice idea back in DOS and Windows 3.1 (if you ever have played with that) but in modern OSes and with modern hardware it's just not gonna fly for you.

Rolf Kalbermatter

Message Edited by rolfk on 11-06-2007 12:07 PM