Article written in 2023.

If Control 4 isn't working with the Engineering Solutions boxes, it is worth determining if the issue lies with C4 or the box itself firstly. Run through all steps HERE to ensure the box is tested directly without C4 and instead via a direct connection from a computer analysed in RealTerm. If any of the responses show random characters it's likely a setting may have been missed.

Once the output response is equivalent to the article then the box itself is fine. Back in C4, ensure the driver is fully up-to-date. Currently it is 3.0.5 but appears to report as 301 within C4. An important setting to ensure that C4 has enabled is within the System Design section of the controller. Ensure that Enable Null Modem on Serial Port # is selected for the appropriate port on the controller. If this is not selected then the output will be operating as IR instead of serial.

Edit: It looks like Null Modem refers to a crossover cable. It has been suggested this was actually to switch between crossover and straight-through cable instead which makes more sense.