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USB Serial Resource not found in LabVIEW

I am having an issue with a USB to serial power supply.  Windows device manager says it is present in the system but LabVIEW doesn't see it.  If I reboot the power supply it will normally fix the issue.  Any ideas why it can't be found in LabVIEW? I have tried refesh but no difference.

 

Matt

 

Matt Fitzsimons
NI Alliance Member
LabVIEW Champion
NI Certified LabVIEW Architect
LabVIEW, LV-RT, Vision, DAQ, Motion, and FPGA
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Message 1 of 8
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I am guessing Windows is shutting off the USB port for "power saving" due to no activity.

 

Buried deep in your Power Options ---> Advanced Settings make sure USB selective suspend setting is Disabled.

 

Here is what it looks like in Windows 7

ap.PNG

 

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=== Engineer Ambiguously ===
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Message 2 of 8
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It was set to enabled so I disabled it.  I will see if this fixes the issue.  Thanks for your suggestion!

 

Matt

 

Matt Fitzsimons
NI Alliance Member
LabVIEW Champion
NI Certified LabVIEW Architect
LabVIEW, LV-RT, Vision, DAQ, Motion, and FPGA
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Message 3 of 8
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Also in the device manager check all of the "root hub" power management tabs and uncheck "allow the computer to turn off this device to save power"

 

Again in Windows 7 it looks like this

ap2.PNG

 

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=== Engineer Ambiguously ===
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Message 4 of 8
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Still having issues on PC reboot finding the TDK power supply.  I will contact the manufacturer on Monday.  Maybe a firmware issue?  Thanks for your help.

 

Matt

 

Matt Fitzsimons
NI Alliance Member
LabVIEW Champion
NI Certified LabVIEW Architect
LabVIEW, LV-RT, Vision, DAQ, Motion, and FPGA
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Message 5 of 8
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Read the Manual Matt,

 

I recall having a similar issue at first while I developed the P-n-P Project style Instrument Driver for that device.  I don't recall exactly what it was but, there is a switch setting on the back that must not be in the factory default position.


"Should be" isn't "Is" -Jay
Message 6 of 8
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Jeff,

It is a TDK-Lambda Z+ Series Z20-20 programmable power supply. I chose it because there was a LabVIEW driver available. There are no switches on the back and no configuration that says don't find the serial port on reboot. Good point to modify the comm configuration to see if I can find something that does work reliably. It is a USB connection that maps to a serial port. Maybe I will try my own USB to serial converter.

 

Thanks,

Matt

Matt Fitzsimons
NI Alliance Member
LabVIEW Champion
NI Certified LabVIEW Architect
LabVIEW, LV-RT, Vision, DAQ, Motion, and FPGA
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Message 7 of 8
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Ahhhh.  A new version of my old friend.  I have not worked with a Z+ series of that TDK Lambda.  Yes, calling them is a must.   Have a manual and a red pen ready when you call.  And post back.


"Should be" isn't "Is" -Jay
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