Wired Ethernet has been supported since OpenSprinkler v3.2. It's implemented by using an external Ethernet module—ENC28J60 for v3.2 and W5500 for v3.3 and v3.4. If you have OpenSprinkler v3.2 or later and your unit did not come with a wired Ethernet module, you can purchase and install one separately. Refer to this document for installation steps.