ZAF Plus Electronics
The electronics are probably the most technical part of ZAF+ construction. There is nothing overly complex, but it does require carefull planning and a lot of diligent soldering to connect the different electrical components. We therefore advice that you plan ahead. The electronics are comprised of four different components:
- A Raspberry Pi 3 B+ to run the software and control the electronics.
- Two Arduino Megas (Arduino 2560 R3) microcontrollers for the digital devices.
- Several motor controllers to control the various pumps.
- 16 Relay Module interface board to drive current and control the valves.
To summarize the wiring: the Raspberry Pi is connected directly to one Arduino Mega using a USB cable. The two Arduinos are daisy-chained via a serial connection (the whole design can be extended by daisy-chaining more arduinos). The Arduinos are connected the motor controllers through digital pins. The Arduinos control the opening of each individual valve through the 16 relay module. A 12V power supply (at least 10A best 20A) provides power to the electronics, expect the Raspberry Pi and the two Arduino Megas.
The following figure summarises ZAF+ electronic connections:
