I realized I had a problem. Or as many problems as I have planters. The short version is that I need a voltage, going to a probe, coming back out, through a voltage divider to another pin. For those of us at home, that’s two plus one common pin for all the probes. I think I can get away from that through a lot of sizes and multiplexing, but I need to map that out. For one thing, if I want to alternate current direction, to combat etching, I need a common ground on both ends…
Peter's stuff.