Cascade: a hardware alternative to bignums

The Cascade hardware architecture for high/variable precision arithmetic is described. It uses a radix-16 redundant signed-digit number representation and directly supports single or multiple precision addition, subtraction, multiplication, division, extraction of the square root and computation of the greatest common divisor. It is object-oriented and implements an abstract class of objects, variable precision integers. It provides a complete suite of memory management functions implemented in hardware, including a garbage collector. The Cascadei hardware permits free tradeoffs of space versus time.