- Tue Oct 01, 2019 9:19 pm
#83994
The schematic shows pullups to 3.3V, so you need to connect that. Nothing is connected to the 5V pin, so you don't *need* to connect that.
You could connect the motor supply VM to the 5V pin (via a diode, as rudy said, to keep noise from the motor(s) out of your 5V supply) to run the motors from the 5V supply, assuming your 5V supply can provide enough current for the motor(s) and whatever else is connected to that. Typically, that would be your D1 mini itself, whose 3.3V supply is derived from the 5V supply. If your 5V supply isn't powerful enough, then starting the motor(s) would cause the 5V supply to sag to a lower voltage. If that voltage gets down below 3.3V, then the D1 mini might reset. Probably that would mean the motors would stop, and then your program would start running again as the supply voltage recovered. Restarting the motor(s) would take you round this cycle again.
If you have a separate supply to run the motors on (e.g. batteries, or a 12V supply), then VM and GND need to be connected to the second supply's + and - terminals. You could also connect a 12V->5V buck converter's input to your 12V or battery supply, and connect its output to the 5V pin to run your D1.