Babbage´s Analytical Engine Plans 28 and 28a. The programmer´s interface

Author

Bromley, Allan G.

Author_Institution

Sydney Univ., NSW, Australia

Volume

22

Issue

4

fYear

2000

Firstpage

5

Lastpage

19

Abstract

Between 1843 and 1846 Charles Babbage worked intensively on the design of Plan 28 of his Analytical Engine. Most of his effort was devoted to the development of the great operations of multiplication, division, and addition/subtraction of strings of operands. These were carefully elaborated, and the implementations of both multiplication and division have a decidedly modern flavor. Some of Babbage´s time was spent on small operations including implementations of conditional branches. Here we find revealed for the first time a workable, if unpolished, user instruction set for the programmer of his Analytical Engine.

Keywords

analogue computers; arithmetic; history; instruction sets; mathematics computing; user interfaces; Babbage Analytical Engine Plan 28; Charles Babbage; addition/subtraction; conditional branches; division; multiplication; programmer interface; small operations; strings of operands; user instruction set; Arithmetic; Automatic control; Computer architecture; Concrete; Difference engines; Information analysis; Programming profession; Steady-state; Terminology;

fLanguage

English

Journal_Title

Annals of the History of Computing, IEEE

Publisher

ieee

ISSN

1058-6180

Type

jour

DOI

10.1109/85.887986

Filename

887986