Transmitter, sensors, and valve setup.

Finished up the next phase of the project.  I've wired up and started testing the new light level sensor(TSL13S),  as well as added sensing for the valve current state(on or off) and now detect when the the charging circuit is active.

I've also wired up the TIP112 darlington transistor, replacing the ULN2803 darlington array.  As the array was taking up a bit too much realestate on the breadboard which was needed for the detection circuit of the charge enabled indicator, it had to be removed.

The last part in this is changing the logic that I had planned to use for the on/off switch. Instead of detecting the moisture level while the water is flowing, this will be a timed event. The sequence will go as follows.

1. Detect low moisture level.
2. Open valve to let the water flow for X seconds(30 initially).
3. Start cooldown period of 2 minutes to let the water permeate the soil.
4. Repeat steps 1 and 2 until saturation reaches the predetermined level.

This should prevent oversaturation of the soil and give a nice even moisture level.

Other things that will be taken into account on the above, is light level(water in the morning or at least during sunny times) and making sure the battery is fully charged and can power the servo controlled valve.

Finally, I'll have a manual control valve inline and left open for use when/if there is a battery/circuit failure.

After coding the valve control I'll be able to start testing the setup and track how well it works based on the set of data that is transmitted throughout the process.  Exciting!!!