The DPS5005 contains a USB/RS485 interface so both PSU’s can be remotely controlled. I want to use this option to create a Wifi based PSU. ESP-Wroom-32 do have 3 UART’s, so we can still keep UART0 for programming and use UART1 & 2 for each board. I do however notice on the original USB board that the vendor used photo couplers and I think that is a good idea. I would otherwise struggle with ground between the two PSU units that needs to remain isolated from each other.
The only concern here is that the opto coupler’s have limited data rates, but DPS5005 comes pre-programmed with a fixed baudrate anyway. The schematics above is just one I found and modified in Powerpoint of all things. I am not sure ESP32 is capable of driving an opto-coupler directly, so we might need transistors. I obviously also need a separate PSU as I can’t feed from any of the main ones. The signal from DPS5005 include a 5V PSU to feed that side, so we will be using 3 separate PSU’s on this board.