OpenCoral was initially designed to be an Open Source Hardware aquarium controller. It has several key components:

• Various modules (such as the TipTop)
• Communications standard – OCNet, based on CAN
• Controller firmware

The problem with OpenCoral was its slightly myopic vision. It was an aquarium controller first, and only. The TipTop module is the epitome of this: great design for a aquarium top off controller (on incredible steroids), but way too specific for level control and IO control. Instead, I am remodeling the OpenCoral concept based upon PLCs (Programmable Logic Controllers), more discrete, simpler, and malleable logic blocks. I’m head deep in the various standards surrounding them (such as the venerable IEC 61131), and from some real world experiences utilizing them.

Another issue was the slightly more advanced hardware required by OpenCoral (ARM processors, etc), primarily for OCnet. I am trying to simplify the integration work for the future products, and have settled on a hybrid ModBus RTU and OCnet interface. On the ModBus RTU front, as its such a simple protocol, an average AVR micro-controller suffices. Familiarity in the hobbyist circles is high with the AVR, and tools abundant.

Lastly, the name OpenCoral is of course utilized by a separate Open Source project. Name tweaks are welcome.