[Nut-upsdev] Liebert PowerSure PSA 500

[Charles Lepple]

On 9/7/05, Peter Selinger <selinger at mathstat.dal.ca> wrote:
> > -- hidups driver can't connect to the UPS anymore:
> >       # bin/hidups -DD -a PowerSure
> >       Network UPS Tools: HID UPS driver 0.13 (2.1.0)
> >
> >       Warning: This is an experimental driver.
> >       Some features may not function correctly.
> >
> >       debug level is '2'
> >       hiddev path open /dev/usb/hiddev0: No such device
> 
> I suspect that unlike newhidups, the old hidups actually relies on the
> kernel driver, as it is probably the kernel driver that provides the
> /dev/usb/hiddev0 interface.

suspicions confirmed - hidups uses /dev/*/hiddev0, and newhidups uses libusb.

For the record, the problem with the kernel HID interface is that it
does not allow access to nested HID elements as seen in many high-end
HID UPSes. (I think this has been fixed in later 2.6.x kernels, but
don't quote me on that.)

-- 
- Charles Lepple