Digital Arithmetic

192

c ~ A ~'v [~ ~ 4

Multiplication

4o t ~2

Two's Complement

We now describe the modifications required when the operands and the result

are in two's complement representation. As indicated by the algorithm shown

at the beginning of the chapter, one possibility is to transform the operands

into sign-and-magnitude, perform the mtiltiplication, and then transform the

result. However, this is not necessary when using the add-and-shift algorithm. In

this case, the following modifications to the sign-and-magnitude algorithm are

suitable.

First, for operands of n bits (in two's complement representation) the range

of the product ...