Serial Fathom S speed

Is the serial over 200m on fathom s real time or is there lag? I am communicating between 2 raspberry pis. I am wondering if i could send motor control over signals over it.

It is real time, and it can be used for motor control signals.

The Fathom-S boards use RS 422 communications: Fathom-S Usage Guide

Thanks!

I was wondering, because the pi works on 3.3v and the fathom-s works on 5v I would need to use a logic level converter, (https://www.sparkfun.com/products/12009) would this affect speed?

The Fathom S doesn’t use a Raspberry Pi, it connects directly to the Pixhawk: Fathom-S Usage Guide

I am using a serial connection between the pi’s over the cable using the fathom s. Not connecting it to a pixhawk