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USB to serial problems

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Hi,

I want to communicate with a device using serial communication (device=Extramess micrometer). I use Labview 7.1 and Visa 3.4

When I connect to COM1: no problem.
However when I use a serial-to-usb interface I don't get any communication. Other devices work well on the same serial-to-usb device so it probably is not a hardware problem.
Any suggestions on how to tackle this problem?

Thanks,

Steven


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Steven,

Do you get any errors?

Does the device "steal" power from the serial port? I ran into this with a device. The USB to Serial device only powered up the handshakng lines (where the power is picked off) when it was sending or reading data. Result: Send command to device. Power down device. Device forgets command. Power up device and try to read response. No response because the device had been powered down. Not easy to trouble shoot!

Work around: Create VISA session and initialize port. Use property node to Assert Handshaking lines. Do reads and writes in main program. When finished Unassert lines and close VISA session.

Lynn
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Hi.

I'm trying to write a LabVIEW VI to read the values from my Mahr extramess and marcator.

I can open the devices an read out the data from the eeprom (name, type etc.) but I can't read the measurementvalues?

Can any one help? Or give me a hint whats going wrong?

Thanks!

 

-Whiteman-

 

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