History and Features of VHDL The Requirement The development of VHDL was initiated in 1981 by the United States Department of Defence to address the hardware life cycle crisis. The cost of re-procuring electronic hardware as technologies became obsolete was reaching crisis point, because the function of the parts was not adequately documented, and the various components making up a system were individually verified using a wide range of different and incompatible simulation languages and tools. The requirement was for a language with a wide range of descriptive capability that would work the same on any simulator and was independent of technology or design methodology. Standardization The standardization process for VHDL was unique in that the participation and feedback from industry was sought at an early