MobiFlight Community Support

Welcome to the forum for MobiFlight! Feel free to reach out to the community in case you have questions, issues or just want to share great ideas or details about your latest home cockpit project.

You like MobiFlight? Donate via PayPal and support the MobiFlight development. Thanks! 

05/03/2024 - This forum is read-only

The community support for MobiFlight has moved exclusively over to our Discord server. Register for free and enjoy more interactive functions like image and video upload, voice chat. More than 7,000 registered users around the world make it a great experience!

See you on our MobiFlight Community Discord server.

A HUGE Thank You to everyone who participated in the forum, especially obviously to Pizman and Stephan who did an outstanding job over so many years providing an incredible service to the MobiFlight community.

The forum is still providing a lot of good content, hence we keep this information accessible.

Posts: 8
Hi Guys, I was wondering if it is ok to power multiple arduinos from one power unit. My main concern is the ground. Is ok for all the GND's to be linked as I also would be powering stepper motors and 7 seg LED's. I'm not worried about the amount of devices being powered just if it's ok to have GND's from different arduinos

2018-08-22 14:02
From: EDDG, Germany
Posts: 1867
Hi Coco,

I think it can not be mentioned often enough. GND is the common unified (basic) potential to which all other potentials refer.

Assuming you want to connect to a MEGA, which has its GND, a second MEGA or record in the system, then it is essential to connect the GND of the 2nd MEGA with the GND of the 1st MEGA, so that both MEGA one have common potential.

It is the same with other components connected to the system. Always connect to GND.

It may also be that GND is already connected via the USB bus, as it is with a HUB. An (additional) direct connection to the GND does not hurt and you are always on the safe side.

If components are to be connected to an external power supply, the GND must also be connected here. This is especially true when data is being transferred. The transmitter outputs the data with a certain voltage (amplitude). How should the receiver know how big this data is (amplitude) if it has no reference potential?

As I said, who has a multimeter, can measure whether GND is already supplied via the USB potential. However, if other components are added that are not connected to the USB bus, the GND MUST be connected.

As a thought, anyone can remember that it takes the GND, if you want to have a closed circuit, because only then all components work with the same reference potential.

You can also remember: In case of doubt, always install an additional GND cable.
Stephan (Time: UTC+2)
2018-08-22 15:07
Posts: 8
Many Thanks Stephan:)
2018-08-22 15:35