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PT-104 USB issues (UsbPt104Enumerate)

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PT-104 USB issues (UsbPt104Enumerate)

Postby danacres » Thu Jan 10, 2013 9:00 am

I'm trying to use two of these devices in parallel over USB but need to use the UsbPt104Enumerate function to properly address them. One device works fine as an example is provided.

I've tried to follow the programming guide http://www.picotech.com/document/pdf/usbpt104pg.en​-2.pdf but frankly I'm not sure what I'm doing.

The result is always either a crash or a blank string.

Has anyone successfully used two of these devices in parallel?

Could someone provide a working example for all the library calls rather than just the basic ones?

Thanks in advance

DA

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Re: PT-104 USB issues (UsbPt104Enumerate)

Postby Martyn » Mon Jan 14, 2013 7:41 am

I haven't tried in Labview but have in C so it should work. If you would like to post your vi we can take a look for you.
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Re: PT-104 USB issues (UsbPt104Enumerate)

Postby danacres » Mon Jan 14, 2013 10:16 am

Thanks for the reply.
I have just got the code working without the UsbPt104Enumerate function

There is a mistake in the example VI for USB comms where the USBPT104Open DLL call has an I32 wired to Serial instead of a proper string constant of the Serial No. This lets me successfully communicate with two devices in parallel when fixed.

As a curiosity when I rearrange the code more tidily in labview (ie put the repeated DLL calls in a loop instead for sequence) I am stuck only being able to read a single device. Even stopping the VI and restarting won't fix that. For some reason the explicit instance of each of the DLL nodes is required to make the thing work properly.

Cheers

DA
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