Addition and subtraction device incorporating at least one binary operator, and decimal operator including such a device

摘要

The invention relates to a device carrying out the addition and subtraction of decimal numbers. The device comprises as many sub-units (B) as the decimal numbers comprise digits. Each of these sub-units comprises a binary operator (OB) which receives two binary-coded decimal digits (01, 02) and which performs the bit by bit addition and subtraction of these input digits, and a read-only memory (M) which receives the digit (S) furnished by the preceding binary operator (OB) and which, for each digit, furnishes, on external command (C1, C2), a value (R) which is the result of the relevant operation and is expressed either in binary form or in the form of a predefined decimal code. The device applies to the construction of a decimal operator. IMAGE