An economical approach for small sized automation tasks

Introducing automation distributed in small (sub-) systems will be an enabler to more functions, comfort, energy savings, growth of quality and other advantages in many fields so far not at all or only sparsely or automated. The latter is the case in small buildings and private homes. Here it is essential that the extra automation equipment brought in is sparing with energy and other resources. This is essential for acceptance per se. And it would make no sense if the costs of equipment exceed the savings achieved by automation. Using common lean micro-controllers or tiny computer/con-troller boards usual in trade with open software would accomplish the energy and cost savings on the one hand. Insisting on established automation standards on the other hand forbids their naive (wide spread) use. To handle this conflict the specifications for a suitable approach is presented. This specification was realized in an evaluation board as a proof of concept. The hardware complexity of interfaces goes far beyond the majority of small computer/micro-controller boards and is comparable to industrial PLC (programmable logic controller, small industrial automation system) process I/O (input/output) modules. The complexity of the software stems from bringing PLC tasks, services and protocols to a small micro-controller as well as from some sophisticated algorithms to make that work on quite small computing power.