1. University of Utah 1 Fortran Assignment Due tonight @ 7:30pm Questions?

2. University of Utah 2 Early 1960's Mainframe Companies Snow White (IBM) Seven Dwarfs -Control Data, Honeywell, Philco, Burroughs, RCA, GE, NCR

3. University of Utah 3 IBM in 1961 7090/7094 -large scientific mainframe 1401 -small mainframe 7070 -“business” version of 7090 1620 -another small mainframe

4. University of Utah 4 IBM in 1961 7090/7094 -large scientific mainframe 1401 -small mainframe 7070 -“business” version of 7090 1620 -another small mainframe ALL INCOMPATIBLE!

5. University of Utah 5 SPREAD Committee at IBM (1961) -Current machines not scalable -What to do about it?

6. University of Utah 6 The Answer One unified product line -for business AND science “Bet the company”

7. University of Utah 7 System/360 A family of related machines -25:1 performance ratio All binary-compatible with each other!!! -Same executables run on each model of 360

8. University of Utah 8 How? Microprogramming -Same instruction set -But implemented differently for each machine!

9. University of Utah 9 Gallery

10. University of Utah 10 10 Gallery

11. University of Utah 11 11 Gallery

12. University of Utah 12 12 Lasting trends System/360 used 8-bit “bytes” 32-bit word length General-purpose registers

13. University of Utah 13 13 EBCDIC “Extended Binary Coded Decimal Interchange Code” Two standards -ASCII for minicomputers -EBCDIC for mainframes

14. University of Utah 14 14 Emulators 360 included emulation modes for -7000-series -1401 Customers could migrate existing applications -Sorry, Honeywell!

15. University of Utah 15 15 Operating Systems OS/360 -Too late! Stopgaps -BOS, TOS, DOS

16. University of Utah 16 16 Famous People Gene Amdahl -“Amdahl's Law” -Principle designer of System/360

17. University of Utah 17 17 Famous People Fred Brooks -“The Mythical Man-Month” Based on experiences writing OS/360

18. University of Utah 18 18 Summary System/360 -extremely successful! -first “line” of computers -established many current conventions Direct ancestor of IBM's current mainframes!

19. University of Utah 19 19 Next Homework

20. University of Utah 20 20 Multimedia

21. University of Utah 21 21 Friday Guest speaker: Lee Hollaar

22. University of Utah 22 22 “Test Question” On a scrap of paper, write a question that encapsulates one of the points from today's class, and turn it in. (Put your name on it!)