VHDL is a critical language for RTL design and is a major component of the $200+ million RTL simulation market¹. Many users prefer to use VHDL for RTL design as the language continues to provide desired characteristics in design safety, flexibility and maintainability². While VHDL has provided significant value for digital designers since 1987, it has had only one significant language revision in 1993. It has taken many years for design state-of-practice to catch-up to and, in some cases, surpass the capabilities that have been available in VHDL for over 15 years. Last year, the VHDL Analysis and Standardization Group (VASG), which is responsible for the VHDL standard, received clear indication from the VHDL community that it was now time to look at enhancing VHDL.

In response to the user community, VASG initiated the VHDL-200x project3. VHDL-200x will result in at least two revisions of the VHDL standard. The first revision is planned to be completed next year (2004) and will include a C language interface (VHPI); a collection of high user value enhancements to improve designer productivity and modeling capability and potential inclusion of assertion-based verification and testbench modeling enhancements⁴. A second revision is planned to follow about 2 years later. This paper focuses on the 1st revision enhancements.