A simulator for on-line arithmetic

On-line arithmetic is a special class of serial arithmetic where algorithms produce results with the most significant digit first during the serial input of the operands. Speedup of computations can be achieved by overlapping or pipelining successive operations with small delays. This paper describes the design and implementation of a simulator for on-line arithmetic algorithms. The simulator was designed primarily to serve as 1) an experimental tool for synthesis of on-line algorithms; 2) a performance evaluation tool of on-line arithmetic; 3) an on-line calculator in solving some problems involving linear and non-linear recurrences. The simulator evaluates arithmetic expressions given in a highly functional form. Presently, the set of operations supported include addition, subtraction, multiplication, division, and square root. Several examples are presented in this paper to illustrate the usage of the simulator. The simulator package is implemented in ‘C’ language on a VAX 11/780 system.