Please I'm new to Arduino and I need assistance. I'm working on a project which makes use of the ultrasonic sensor to make a certain pin high if a certain distance is attained. When I used the USB port to power it up it worked fine. When I use external power(tried two different 9V microphone battery) it's not giving desired result. Now I want to try using just the Atmega328P on the board externally(separately from the Arduino).
- What could be the cause of the malfunction when I use external 9V battery
- what voltage should I connect to the VCC of the Atmega cos I'm scared of damaging it.
- Am I going to power the ultrasonic sensor with an entirely different source from the VCC or I can tap from that same VCC source.
- Any other information I need to know using the ATmega on its own