# GNSS Compass RTK (2-pin) RS-422 Connection

The GNSS Compass modules drive longer cable lengths than can be done reliably with TTL-level serial signals. The ROVL-ethernet PC board is set up to accommodate this.

The RTK (2-pin) connections use RS-422 signaling to drive the required line lengths. The Base unit transmits only and the Rover unit receives only.

{% hint style="warning" %}
Note the pinout of the Rover cable 2-pin connection is reversed from that of the Base.
{% endhint %}

<figure><img src="/files/idZuvDdbYZO0Ju6SKRP9" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/xPGJ2o4dRMID7GDMl9Jk" alt=""><figcaption></figcaption></figure>


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