1. COMS 161 Introduction to Computing
Title: Computer Organization
Date: March 28, 2005
Lecture Number: 28

2. Announcements
Final draft research paper
Due Friday 4/1/2005

3. Review History of computers Pascal Baggage Lovelace Herman Hollerith
“Pascaline”
Baggage
Difference and Analytic Engine
Lovelace
First programmer (Analytic engine)
Herman Hollerith
Census worker
Founded company that became IBM

4. Outline Computer Systems Mechanical computers
Pascal
Babbage
Hollerith
Mechanical and electrical
Electromechanical
Harvard Mark I
Electronic
ABC, ENIAC, EDVAC

5. Computer System Electromechanical computer
During the late 1930s punched-card machine techniques had become so well established and reliable
Howard Aiken, in collaboration with engineers at IBM, undertook construction of a large automatic digital computer based on standard IBM electromechanical parts
Handled 23-decimal-place numbers

6. Computer System Electromechanical computer IBM called the machine
automatic sequence controlled calculator (ASCC)
It is better known
Harvard Mark I,

7. Harvard Mark I 1944 51 feet long weighs 5 tons
incorporates 750,000 parts

8. Harvard Mark I

9. Computer System Electronic Computer
Fastest, but still performs simple steps
One of the great illusion of the computer:
Lots of simple steps performed quickly enough make the computer appear complicated

10. Computer System Electronic computer
John Vincent Atanasoff ( )
Clifford Berry ( )
Built the world's first electronic-digital computer at Iowa State University between 1939 and 1942
The Atanasoff-Berry Computer (ABC) represented several innovations in computing
a binary system of arithmetic
parallel processing
regenerative memory
separation of memory and computing functions

11. Electronic Computer
Atanasoff performed intensive computing while working on his doctorate in theoretical physics (late 1920’s – 1930)
The forgotten father of computing
Faculty member at Iowa State College in mathematics and physics
In 1937 worked out the design
In 1939 he hired a student Clifford Berry to help him construct the machine
By 1941 they had a working machine

12. Electronic Computer
Clifford Berry with ABC in 1942

13. Electronic Computer
Replica of ABC

14. Electronic Computer
In 1946, John Eckert and John Mauchley built Electronic Integrator and Computer (ENIAC)
Specific task was compiling tables for the trajectories of bombs and shells
It contained roughly 18,000 vacuum tubes
Measured about 2.5 meters in height and 24 meters in length
The machine was more than 1000 times faster than its electromechanical predecessors
It could execute up to 5000 additions per second

15. Electronic Computer
ENIAC
The first general purpose computer

16. Electronic Computer
The ENIAC machine occupied a room thirty by fifty feet
The controls are at the left
A small part of the output device is at the right

17. Electronic Computer

18. Electronic Computer Improvement ideas developed as ENIAC was built
The stored program concept among them
John von Neumann
EDVAC
A new machine with improvements over ENIAC
The first stored program computer

19. Enter the Sharks
Mauchley filed and received patents for the first general computer
However
Mauchly visited Atanasoff in 1941 and was inspired by Atanasoff's work
In 1941 Atanasoff knew more about basic elements of electronic computation than Mauchly and openly shared this knowledge
Enter the lawyers
Early 1967

20. Sharks
October 19, 1973
Judge Larson had ruled that John Vincent Atanasoff and Clifford Berry had constructed the first electronic digital computer at Iowa State College in the period
He had also ruled that Mauchly and Eckert, who had for more than twenty-five years been feted, trumpeted, and honored as the co-inventors of the first electronic digital computer
Were not entitled to the patent upon which that honor was based

21. Sharks October 19, 1973 Judge Larson also ruled
Mauchly had pirated Atanasoff's ideas
For more than thirty years had palmed those ideas off on the world as the product of his own genius