I got the controller hardwired in and started to troubleshoot some stuff.
I totally forgot GPIO 0-8 is active high on boot. To get active low I need to use GPIO pins 23, 24, 25 and 26. Also the Relay board is inverted so I need to add a hex inverter with a 74HC14. Also wouldn’t hurt to add a buffer to protect the Pi.
I copied the schematic from the Relay board. I took a educated guess on the resistor values and picked my favorite BJT NPN Transistor. I also added a 74HC245 buffer and a 74HC14 Schmitt Triggered Hex Inverter.
If I was to do a PCB I would include the power supply as well.
Quick and easy example. Typical linear head end with Buck Converters to dial in the correct voltages along with extra points to power up additional sensors.
Anyway, I need to make the changes to my setup so I can finally water the lawn.
The IT Garage 