[Nut-upsdev] Tripp-Lite SMART1500LCDT

Stuart D. Gathman stuart at gathman.org
Mon Aug 8 15:42:03 UTC 2016

On Sat, 6 Aug 2016, Marco Walther wrote:

>> >  I also bought a USB2-HUB-AG7, but the new black version (of the *same*
>> >  model# - arrrrgggghhhh) no longer implements PPPS.  Only the old silver
>> >  version does.  What is the point of a model# if you can't count on the
>> >  functionality?
>> >
>>  Mine even says v1 on the type sticker:-( but it's black as well. So I'll
>>  see how things behave once I loose the UPS connection and do a `hub-ctrl
>>  power off->on'. I'm not really interested in the power off, just in the
>>  reset;-)

> OK, that did not work:-( Neither the `hub-ctrl power off->on' nor the 
> unbind->bind of the hub did reset the USB connection enough that the OS would 
> see the UPS again:-(
> Stuart, did you  find an USB hub which can actually switch the power? 
> Otherwise, I'll probably go down the road of creating an Arduino-based 
> power-switch at least as test setup.

Yes, the Linksys USB2HUB4 works perfectly as described in

Also, known working hubs are listed at

I have been through several cycles of the Tripplite USB locking up,
I cycle the power on the port remotely, and the Tripplite USB comes
back online!  Plus, working PPPS can turn LED lights on/off and do
other handy remote control things.  Power cycling the USB port
can reset other buggy USB equipment as well.

 	Question for the List

How that I've verified that the port power cycle works to reset the
Tripplite, where is the best place to make this happen automatically?

 	1) need to determine the address of the hub and the port that
 	the UPS is plugged into.

 	Currently, I have to parse output of lsusb to find bus and
 	device of Tripplite.  Then parse lsusb -t to find bus and device
 	of the hub, and the port the Tripplite is in.  Is there
 	a cleaner way?

 	  a) Is it worth adding code to usbhid-ups to do this power
 	  cycle?  Or is it best done in scripts for the broken UPS
 	  models that need it?

 	  b) Once the Tripplite hangs, it will no longer enumerate, so
 	  I need to store the bus,dev,port determined above for use
 	  when it hangs up.

 	2) need to notice that UPS is gone

 	  a) I could use NOTIFYFLAG EXEC.  The script would check that
 	  lsusb no longer shows the Tripplite, then do the recovery

 	      Stuart D. Gathman <stuart at gathman.org>
"Confutatis maledictis, flamis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.

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