[Nut-upsuser] howto setup BNT-1500AP on gentoo

Charles Lepple clepple at gmail.com
Tue Dec 12 14:23:50 CET 2006

On 12/12/06, Arjen de Korte <nut+users at de-korte.org> wrote:
> >> data receiving error (-1 instead of 16 bytes)
> [...]
> > The logfile '/tmp/powercom.log' will help narrow down which code path
> > is returning '-1'.
> Looking at the sources, it is quite obvious where this error occurs (in
> upsdrv_updateinfo). Sending a command to the UPS apparently is not a
> problem, but the '-1' indicates that the UPS is not responding at all
> (most likely, ser_get_buf_len times out).


"which code path" was probably not the best choice of words; I meant
that there are several places where the timeout (or other error) could
have been detected while trying to run "upsdrv_updateinfo".

Vitaly just sent the result of strace which confirms that the UPS does
not send anything in reply to a 0x01 byte.

However, there is still a chance that it is a protocol mismatch, or
that the serial control lines need to be set some other way.


This web page shows a blue cable with the management software:


I'm going to guess that there might be a difference between the cable
that ships with the UPS (for basic monitoring and shutdown via
genericups), and the one which can manage the UPS (e.g. provide
runtime estimates, adjust variables on the UPS, start battery tests,

- Charles Lepple

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