Project:Door sensor

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Door Sensor

Aim

To tell the state of the (front) door without having to physically be there/see it. More generically, a binary input that is on the network.

How it works

  • You can create Ethernet loop back devices by shorting a couple of pairs on Ethernet cables as per http://erikugel.wordpress.com/2011/09/14/making-an-ethernet-loopback-adapder/
  • By opening and closing one pair you can bring a network interface up/down
  • A micro switch has been mounted into the door frame at the top and brown/white cable run to choc blocks, and then a network cable run back to Cisco2 switch, port 42

Cisco port need some configuring:

interface GigabitEthernet1/42
no keepalive
speed 100
duplex full

Things it doesn't interact with

This has nothing to do with:

  • Doorbot
  • Spacecensus
  • Alarm Cabling

How do I interact with this?

?doorstatus on IRC will responsd with "Door closed" or "Door open"

?doorsnmp will do a more advanced check, with SNMP polling and respond thusly: Door is closed (last movement was on 18/11/2012 at 20:29:29)

The ?doorsnmp (/usr/share/irccat/doorsnmp.py on babbage) code isn't the greatest, I'm sure someone can improve it.

What next?

  • Tidy up the script that tells IRC the status. At the moment it is the quickest dirtiest python you will ever see
  • Add more doors! - Build a complete building management system that has the status of all infrastructure
  • Log/graph it in Cacti?