Like the subject, but I can’t get it to work. The usb board connects fine and its working OK. Same for the relais board, it works just fine.
I’d like to flip the relais on the relais board zo I connected the usb board to the relais board by connecting the digital outputs to the relais board terminals. The VB terminal goes from the relais board onto the clamp on the USB and both the GND’s are connected together between usb and relais board. When flipping the digital outs on the usb board nothing happens.
What am I missing?
TIA!