Develop Parallel Arithmetic Operations for Binary Modified Signed-Digit System Using Two-Step Algorithm

An optical computing system is expected to be a powerful information processing system that takes full advantage of optics, such as parallelism, high speed, and large information capacity. Therefore many suitable optical number systems have been developed by many research to exploit the inherent parallelism of optics to developed parallel arithmetic operations . In this paper we used binary modified signed-digit (BMSD) number system and available recoding method to generate a simplified binary MSD addition/subtraction truth table to obtained a parallel two-step algorithm in which the carry chain was generated during the addition operation and the borrowing chain was generated during the subtraction operation that will be stopped after two steps, the addition and subtraction operations will be completed independent of the number of digits in each operand. Also this paper involve limitation for the minterms that used in the logical processing for the addition/subtraction truth table.