Patent ID: 7257465

Claim:
An irrigation controller for controlling the operation of an irrigation system, said controller comprising: a controller housing having a front cover door and a rear cabinet portion; a base unit mounted within said housing and including a control panel removably mounted to the rear cabinet portion and a back plane circuit board mounted to the rear cabinet portion and releasably connected with said control panel, said back plane circuit board including a plurality of discrete electrical output connector sets communicating with a first microcontroller, said removable control panel including said first microcontroller for sending control signals to said back plane circuit and capable of receiving and storing irrigation system programs input into said first microcontroller; a base module removably mounted within said rear cabinet portion and electrically coupled with said back plane circuit board through one of said plurality of output discrete electrical output connector sets, said base module including drivers and output switches for actuating irrigation valves in accordance with control signals received from said first microcontroller; and an expansion module removably mounted within said rear cabinet portion and electrically coupled with said back plane circuit board through another of said plurality of discrete electrical output connector sets, said expansion module including a second microcontroller capable of communicating with said first microcontroller, and drivers and output switches coupled with said second microcontroller for actuating irrigation system valves, said first and second microcontrollers operating together in order to carry out irrigation system operations not capable of being performed by said first microcontroller alone, wherein the other of said plurality of discrete electrical output connector sets to which the expansion module is electrically coupled may be any one of said plurality of discrete electrical output connector sets capable of being coupled to a given expansion module independent of the electrical coupling of another expansion module to another of said plurality of discrete electrical output connector sets.