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Chapter 4
The Von Neumann
Model
Based on slides © Mc Graw-Hill
Additional material © 2004/2005 Lewis/Martin
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CSE 240
Warning!
This is a bottom-up course
•No secrets, no magic
e.g., gates build on transistors, logic c ircuits from gates, e tc.
But… This is a top-down lecture
•You’ll have to trust m e for a couple slides
•Start with very a bstract discussion of computer architectur e
•Meet with Chapter 3 m aterial soon
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CSE 240
What Do We Know?
A LOT!!
•Data representation (binary, 2’s complement, floating point, …)
•Transistors (p-type, n-type, CMOS)
•Gates (complementary logic)
•Combinational logic c ircuits (PLAs), memory (latches, flip-flops, …)
•Sequential logic circu its (state machines)
•Simple “process ors” (programmable traffic sign)
What’s next?
•Apply all this to tradit ional computing
•Software interface: in structions
•Hardware implementa tion: data path
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CSE 240
A Little Context
1943: ENIAC
•First general electronic computer (Pre sper Eckert and John Mauchly)
(Or was it Atananasoff i n 1939? Or Konrad Zuse in 1941?)
•18,000 tubes (had to replace 50 a day!)
•Memory: 20 10-digit numbers (decimal)
•Hard-wired program (via dials, switches,
and cables)
•Completed in 1946
1944: Beginnings of E DVAC
•Among other improvements, includes program sto red in memory
•Gave birth to UNIVAC-I (1951)
•Completed in 1952
See Eniac by Scott McCartney
