John Goerg <john at krwc1360.com> writes: > David Dyer-Bennet wrote: > <snip> > > Note that my two UPSs use "stupid" communications protocol, not > > "smart". There's actually a diagram in the Back-ups 600 manual > > showing what each connection on the 9-pin port is (I believe from > > reading how-tos and things that they 600 and 650 are about the same in > > this; the 650 manual doesn't actually give a diagram, though). > > The diagram actually looks like it would be better off with a pull-up > > resistor on the line it uses to signal line power fail (the 600 > > manual, at least, describes that line and two others as open-collector > > outputs). > > It seems like apples and oranges here. Sounds like the ups's are > discrete type outputs (open collector) designed to run an external > alarm, and you want to hook it to a serial port. Won't work. Some > ups's are switchable between serial and discrete (stupid) outputs. > Or maybe some pins are for serial and others are alarm outputs. Best > ups did this for a while. If you can set it for serial try a null > modem adapter or cable. No, the normal way to monitor the discrete ouput (stupid) UPSs has always been through a serial port (but not with a standard serial cable). There are a bunch of lines you can directly monitor and control on a serial port -- DCD, DTR, DSR, CTS, RI, stuff like that. None of my UPSs are new enough to use actual serial communications. -- David Dyer-Bennet, dd-b at dd-b.net / New TMDA anti-spam in test John Dyer-Bennet 1915-2002 Memorial Site http://john.dyer-bennet.net Book log: http://www.dd-b.net/dd-b/Ouroboros/booknotes/ New Dragaera mailing lists, see http://dragaera.info