[Nut-upsuser] USB/UPS connectivity issue on Intel DP55KG Motherboard

Justin Piszcz jpiszcz at lucidpixels.com
Thu Oct 15 14:12:02 UTC 2009

On Thu, 15 Oct 2009, Charles Lepple wrote:

> On Oct 13, 2009, at 5:55 PM, Justin Piszcz wrote:
>> Hello,
>> I use the following in my ups.conf:
>> # USB:
>> [apc]
>> driver = usbhid-ups
>> port = auto
>> desc = "APC 1500VA"
>> pollfreq = 5
> On NUT 2.4.1 (and some older versions), the pollfreq value determines how 
> often usbhid-ups explicitly requests all of the values; however, the UPS is 
> still free to send interrupt reports at any time within that polling 
> interval, and those reports should be processed more frequently.

> Typically, interrupt reports are sent by the UPS when status conditions 
> change, so the reporting delay for something like a power failure should be 
> well below pollfreq.

> Was there a particular issue that led you to choose "5" for pollfreq? If so, 
> what version of NUT were you using at the time?
Yes, I wanted to be able to see power alerts / events when they were short.
When pollfreq is not set, or if it is set too high (e.g. 30 seconds), I do
not get any e-mail if the power goes out and then comes back on very quickly.

Ok, so is this a bug with the USB chipset used on this DP55KG board or is 
it a problem with nut?  OR did yet another change occur in the kernel usb 
driver, I recall before I had to enable a specific option for other 
problems I used to have on a different UPS 1-2 years ago.


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