[Nut-upsdev] Question on support for Upsonic Commercial UPS CXR 2000 - 2000VA/1200W - Rack/Tower on Freebsd 9.1.

[Charles Lepple]

On Feb 6, 2014, at 8:41 AM, Chris Duffy wrote:

>   0.016485    Trying megatec protocol...
>   0.017411    send: Q1
>   0.252545    read: (244.4 244.4 229.9 028 50.0 2.19 23.1 00000001
>   0.252589    Status read in 1 tries
>   0.252602    Supported UPS detected with megatec protocol
>   1.288032    send: Unknown error
>   1.288085    Permissions problem: Input/output error
> 
Interesting that it gets past the first send/read pair.

> dmesg output:
> 
> 
> ugen1.3: <PPC> at usbus1 (disconnected)
> uhid0: at uhub3, port 1, addr 3 (disconnected)
> ugen1.3: <PPC> at usbus1
> uhid0: <PPC USB UPS, class 0/0, rev 2.00/0.03, addr 3> on usbus1


Well, that's frustrating.

The chain of command is something like this:

NUT USB-based drivers -> libusb -> ugen kernel driver -> device

The uhid driver tries to offer access to HID devices, but most USB devices that were designed to work on Windows abuse the HID protocol to avoid requiring a kernel driver.

There is a "quirks list" that effectively kicks uhid out of the way, and that has been necessary for other UPSes on FreeBSD, such as the following:

http://www.freebsd.org/cgi/query-pr.cgi?pr=134766

I'm not sure of the exact steps to take next, but I can look into it.

-- 
Charles Lepple
clepple at gmail