RS-485 Sprinkler Control: Scaling Irrigation Across the Farm

Building your own sprinkler system controller isn’t that difficult on the face of it, but what happens when your system starts to grow, adding more distant areas? To tackle this, [Vinnie] leveraged the tried-and-true RS-485 differential pairs to communicate reliably with ever-more-spread-out valves on his farm’s irrigation system . The system uses a Raspberry Pi to control when each valve turns on and for how long.