VHDL

Hardware description language, VHDL is another popular alternative for people involved in designing  CPUs, motherboards, FPGAs, and many other types of digital circuitry. VHDL can also work to simulate and test the performance of all designs. 

In computer engineering, a hardware description language (HDL) is a specialized computer language used to describe the structure and behavior of electronic circuits, and most commonly, digital logic circuits. A hardware description language enables a precise, formal description of an electronic circuit that allows for the automated analysis and simulation of an electronic circuit.