Soleyman Shirzadi - Department of Electrical Engineering, Technical & Vocational University, Kermanshah, Iran.
Seyede Tahere Hashemi - Department of Electrical Engineering, Engineering Faculty, Kermanshah Branch, Islamic Azad University, Kermanshah, Iran.
Mohammad Saber Setoodeh Kia - Department of Electrical Engineering, Technical & Vocational University, Kermanshah, Iran.

Since Very High Speed Integrated Circuit Hardware Description Language (VHDL) is one of the most practical languages in the contemporary era, and is considered a high-level language, learning programs which facilitate the relationship between language and the software have attracted the attention of designers. One of the programs and basic commands require for designers is random number for modeling completely randomized time delay in accordancewith reality. VHDL alone does not inherit such capacity. In the present paper, writing command codes which generate randomized numbers require for designer are addressed for including randomized numbers with normal distribution, randomized numbers withexponential distribution, randomized numbers with Gaussian distribution and also VITAL model in the input. Then, these numbers have been transformed in to times and direction of them is investigated in basic digital blocks.

Exponential distribution; Gaussian distribution; Random delay; Uniform distribution; VHDL