README
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