[Nut-upsdev] Re: Serial Ports (Was Re: Common Power Management : NUT and HAL (stage 1))

[Matthew Garrett]

On Wed, Sep 13, 2006 at 09:04:32PM -0400, David Zeuthen wrote:

> Also: we certainly can't run serial PNP probing automatically, only in
> response to a user choice of deciding to probe for serial ports. I say
> this because maybe it will crash some old devices or some that don't
> support Serial PNP. This is correct, yes?

The protocol is designed in such a way that it's unlikely to trigger 
anything bad, but it's potentially possible that some hardware will do 
mad things when standard serial lines are asserted. I've /heard/ horror 
stories that some UPSes will power off when they see a PnP query - does 
anyone actually have a verified case of this happening?

There would certainly be issues doing PnP on a serial port being used as 
a serial console, but that's true of any serial port that's currently in 
use.
-- 
Matthew Garrett | mjg59 at srcf.ucam.org