Cellular-array arithmetic unit with multiplication and division

A number of papers have been written recently describing cellular-array multipliers and dividers. The usefulness of these schemes is in their speed of operation and the simplicity of the array structures. However, the structures are such that multiplication and division require separate arrays and possibly different types of cells. Since the number of cells in an array is proportional to the square of the word length used, it would be a tremendous saving if the multiplier and divider could share a large percentage of the hardware. In this paper, some of the existing multiplier and divider arrays are briefly described, and a new multiplier is developed which has an array structure compatible with one of the dividers. It is then shown how this multiplier/divider can be implemented using Hoffmann cells, requiring considerably fewer cells than two separate units. With the addition of a few more control lines, the array can be operated as a complete arithmetic unit allowing a range of single-precision arithmetic and logical operations and double-precision arithmetic operations.