The use of HDLs (Hardware description languages) allows the design of a considerable variety of embedded systems. As a good example of this we present the flow used in the design and construction of an application specific non-pipelined microprocessor, that will serve as core of a PLC (programmable logic controller) compatible with the programming language IL (instruction list) according to the norm IEC 61131-3. Tests to the design, used platform, resources consumed and relevant conclusions are included about the hardware and software aspects of the implementation.