MSP430F5510 based project that ties into the appartment interphone system. in this case it's an Electra IA01.
it allows the owner outside the building to open the door by following a pre-determined list of actions.

if config.h RADIO option (*) is defined then the door opening is triggered by the following actions:
 - call interphone number
 - wait 2s
 - send a radio signal to a receiver that is tied into the project. the receiver should pull P1.2 low on activation.
 - door opens if the signal was received in the defined time window
 If the radio option is not viable due to poor signal/noise ratio another scenario is implemented by deactivating the RADIO ifdef.
 - call interphone number
 - hang up and call again in the software predetermined timeframe
 - door opens

 the first scenario needs one 12v battery, a 12V one channel RC receiver and transmitter. a chronos watch could be used as the RC remote if the topology permits, see [1], [2]. current consumption is about 110uA@12V.
 the second scenario only needs one 3v 2032 Li cell. current consumption is about 1.4uA@3V. the pcb for this one is to be found in hardware/ip_simple.brd

Pinout:
 - P1.1 - 'ring' detector from interphone 'PX'
 - P1.2 - (optional) radio trigger
 - P1.4 - OPEN
 - P1.5 - TALK
 - P1.6 - (optional) power enable for radio rx system

(*) radio-related code removed

 homepage:        https://github.com/rodan/interphone
 author:          Petre Rodan <2b4eda@subdimension.ro>
 license:         GNU GPLv3
 parts of the code were originally forked from the openchronos-ng project [3]. 

 software requirements:

   msp430 toolchain

[1] http://www.ti.com/tool/ez430-chronos
[2] https://github.com/rodan/openchronos-rfsw
[3] http://openchronos-ng.sourceforge.net