[plug] [OT] Maitec Linx UPS Serial Interface

[ryan at is.as.geeky.as]

With all the recentish talk of UPS equipment I finally got out the ratchet
crimper and constructed the 192VDC battery packs (16x12V SLA batteries in
series) needed for 2 lovely old Maitec Linx UPS units I bought a while ago .
If anyone doesn't know what they are, they used to be manufactured many many
years ago in NSW, have top to bottom heatsinks front and back, provide
full-time mains isolation, allow battery-only invertor starting and just
simply work like a charm.

Now down to business.  Has anyone every touched one of these units,
particularly with regards to the serial interface?  There is an empty
'interface' module socket inside with all the other modules such as boost,
control, synch/byp and inverter but I'm not sure if this is needed for
serial communications or not.  There is a 9 pin serial port on the back of
the 800 unit but not the 1400.  All attempts to coax information out of the
serial port have failed - as have the same attempts on the one with no
serial port :)

This page: http://www.emulab.ee.mu.oz.au/~mick/Personal/UPS/index.html talks
of the 1500 (different to my 800 and 1400) and suggests it has some form of
mini terminal server in it .. i doubt mine are this advanced.

Alternatively I can find a 'nicely marked' mains-bypass output and make the
serial port take whatever pin I desire high/low when the mains fail - if I
did that, can such a signal be detected on a serial port in Linux, or does
actual data need to flow rather than just a simple high/low pin?   The
DTR/CD lines works like that on an RS232 port don't they?  Could that be
detected easily?

Anyone got a clue about any of this?

Ryan