19 Aug 2014

Landscape Irrigation Controller schematic is a work in progress. Human interface will consist of mechanical key input and character display output. There are eight stations each one a triac output for 24VAC. Power is supplied from an external wall plug in type transformer. The transformer will power up to two 24VAC solenoids simultaneously. Internally the controller uses a Microchip PIC18F87K22 as the central "processor". The WiFi module is supplied by Microchip and their standard software stack is adapted to the PIC18F87K22 instruction set.

20 Aug 2014

Schematic progress continues. The micro-controller has been specified and the system requirements, reset circuit, external RTC base oscillator, debug and programming port, Vdd and Vss connections, and Vcap are specified and depicted. Reviewed individual schematic parts depictions for Bill of Materials (BOM) specifications.

20 Aug 2014 1752 PDT

Completed System Design Documentation. This is a work in progress and subject to change. The basic items covered were the Landscape Irrigation Controller (LIC) design concept with inclusion of WiFi module. The connections to and from the LIC are depicted in a block diagram. Standard WiFI and router connections are depicted on page 2. These connections indicate communication to the controller user through the internet or direct connection between the passerby on the street and the LIC. Several methods are depicted on page of how the passerby on the street will be able to communicate with the LIC and/or the controller user. 

20 Aug 2014 1801 PDT

A case and form factor for the LIC prototype enclosure is determined. The deciding factors are environmental protection (the unit may be required to be mounted outside in harsh conditions while undergoing operational testing) and enclosure volume. The enclosure may be required to contain prototype materials during testing and debugging that would not normally be contained in a production unit.

20 Aug 2014 2015

The ports that will function as inputs have been selected based upon the necessity of pull up resistors to define a state when the switch placed on the port is in the open condition. PortB is chosen for the 6 switch inputs. The other two ports, RB6 and RB7 are used with the debugger/programmer clock and data. The SPI ports will be SDO1, SDI1, and SCK1. SS1 will be RF7. PortA will not used and will be output low. The objective is to build a basic landscape irrigation controller with no extra functions that can confuse the test results.