The DC8 is not compatible with the current model Apex or Apex-EL. Only AquaBus and 1Link connected modules are supported.
The ports you called RJ11 are actually RJ45 ports, and they’re used to provide 0-10v variable power to control certain pumps or lights:
See my Apex Hardware Overview article for the full list of compatible modules:
Here's a quick overview of the Apex hardware family: Apex controller (sometimes referred to as the "base module" or "brain") The Apex controller is the primary device that controls and monitors the entire Apex setup. There are two current...
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