EPCCS.ORG webhosting will end on January 1, 2017. Some boards and firmware have moved 
to GitHub and rpubus.org

Shields with RS-422 full duplex communication (RX and TX) and 
a RS-485 half duplex out of band management channel. 

Node boards with embedded bare metal MCU, built-in solar charge 
controller, pluggable terminals for the application interface, headers 
compatible with Arduino Uno (not Mega) shields, and DIN Rail mounting. 

The Sensors [HMLP]T are Capacitive with Thermistors and send a 
pulse over a current loop.  OneShot, and VR (variable reluctance) 
also send a pulse over a loop. TT is yet another.  A node (e.g. 
RPUno) has ICP input(s) to capture the pulse event timing. 

Driver CL8 is used to select power to a loop sensor, while K3 is 
used to latch solenoids.

Copyright (C) 2016 Ronald S Sutherland