Common grounds, Arduino Uno and L298N.

Projects General Guidance
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Hello all,

First time post, I just need some help (at the moment) figuring out power with the Arduino Uno.

I'm using pure data (running on a raspberry pi) to control some motors for a robotics project, and so I'm using the Arduino Uno as the step between, as there seems to be objects to enable that sort of communication. What I'm really confused by is power, and the idea of a 'common ground'.

My plan is to connect the Arduino Uno to the raspberry pi via USB. This way the power supply of the Raspberry Pi will power the Arduino Uno.

Due to the nature of the project, I'm assuming its going to be easier to power the L298N from a separate battery source (could be wrong on this, but so far seems logical for other practical reasons).

If I power the L298N separately, do the grounds of the L298N and the Arduino Uno need to be connected at all? And if so where?

Just want to check first rather than blow something up :slight_smile:

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toddak:
If I power the L298N separately, do the grounds of the L298N and the Arduino Uno need to be connected at all? And if so where?

Just want to check first rather than blow something up :slight_smile:

You need to post a link to the datasheet for the specific L298 board you are using. In general the answer is YES there should be a common GND.

On the L298 boards that I have there is a screw terminal marked GND.

...R

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and so I'm using the Arduino Uno as the step between, as there seems to be objects to enable that sort of communication.

You can control the motors direct from the Pi, their is no need for an Arduino here.
Use the GOIO pins to control the motor driver.