These characteristics combined allow VHDL to implement designs functionally, behaviorally, and architecturally with a minimum of self-documenting code. VHDL design software should acknowledge this, and most tools do. A minimum tool suite consists of a text editor, compiler, simulator, optimizer, and synthesizer. Though text editors and compilers are easily understood, the other tools merit some explanation. A VHDL simulator serves this function by accepting the designers' input vectors and producing simulated outputs.
Simulators commonly display inputs and outputs as a timing diagram.
After verifying the design, the designers choose an IC to accommodate it. The optimizer then performs its task, tailoring the VHDL design to fit the IC chosen. The synthesizer provides the design's final assembly, ready for programming. Programming the IC is often done through a serial interface. This allows for maximum design flexibility and source vendor selection.