EE1301: Intro. to Computer Science

• Browsing the “World Wide Web” with Microsoft Explorer™• File management Microsoft XP Operating System™• Writing documents with Microsoft Word™• Preparing presentations with Microsoft Powerpoint™• Operating on spreadsheets with Microsoft Excel™• Reading and composing electronic mail, “e-mail,” with

Microsoft Outlook™

The students will learn the fundamentals of computer science including:

CIS 106: Intro. to Computer Scienceat Pasadena City College

EE1301: Intro. to Computer Science

EE1301: Intro. to Computer Science

Computer Systems

Computer Engineering

EE1301: Intro. to Computing Systems

The course will introduce the fundamental concepts of computing systems from the machine level to high-level language programming, including:

• transistors and logic circuits• binary arithmetic and data representation• memory and pointer addressing• data types and structures• Assembly Language• C programming

• Quantum Physics (what’s an atom?)

• Material Science (why does doped silicon behave as a semiconductor?)

• Device Physics (how does a transistor work?)

• Circuits (how do we put transistors together to get simple logic functions?)

• Logic Design (how do we get complicated logic functions from simpler ones?)

• Computer Architecture (how do we build a computer from logic functions?)

• Assembly Programming (how do we specify tasks in the form of instructions for the computer?)

• High-Level Programming (how do we specify tasks in a form that can be translated into instructions for the computer?)

Vertical Slice of Computer Engineering

• Quantum Physics (what’s an atom?)

• Material Science (why does doped silicon behave as a semiconductor?)

• Device Physics (how does a transistor work?)

• Circuits (how do we put transistors together to get simple logic functions?)

• Logic Design (how do we get complicated logic functions from simpler ones?)

• Computer Architecture (how do we build a computer from logic functions?)

• Assembly Programming (how do we specify tasks in the form of instructions for the computer?)

• High-Level Programming (how do we specify tasks in a form that can be translated into instructions for the computer?)

EE1301

CS 1901 & CS1902

Vertical Slice of Computer Engineering

No Hamsters, No Magic

Any sufficiently advanced technology is indistinguishable from magic.

– Arthur C. Clarke

Examples of Computing Systems

Are all these systems “equivalent”?

Examples of Computing Systems

Are all these systems “ Turing Equivalent”?

Concepts vs. Jargon

“Now this end is called the thagomizer, after the late Thag Simmons.”

Turing Machine

Turing Equivalence

“It can be shown that a single special machine of that type can be made to do the work of all. It could in fact be made to work as a model of any other machine. The special machine may be called the universal machine.”

– Alan Turing, 1947

“The problems solvable by a universal Turing machine are exactly those problems solvable by an algorithm or an effective method of computation, for any reasonable definition of those terms. .”

– Church-Turing Thesis

Turing Universal Systems

Machine that can execute any C program.

main(){ for(;;){

printf ("Hello World!\n");}

}

Turing Universal Systems

Machine that can execute any Assembly program.

Turing Universal Systems

clock

inputs

),,( 1 nxxX

outputs

),,( 1 mzzZ

memoryelements

),,( 1 kyyY

combinationalcircuit

Synchronous Digital System

Building Digital Circuits

Intel 4004(1971)

Intel “Nehalem”(2008)

~2000 gates

~2 billion gates

1 transistor (1960’s) 2000 transistors(Intel 4004, 1971)

800 million transistors(Intel Penryn, 2007)

Boxes inside Boxes [inside boxes…]

From Chips to Computers

IBM’s Blue Gene: 64,000 Processors

The Computational Landscape

• Abutting true physical limits.

• Cost and complexity are starting to overwhelm.

“There are known ‘knowns’; and there are unknown ‘unknowns’; but today I’ll speak of the known ‘unknowns’.”

– Donald Rumsfeld, 2002

Semiconductors:exponentially smaller, faster, cheaper – forever?

Integrated Circuits

0

1

0

1

0

1

0

1

circuit

1

0

What do integrated circuits do? • accept zeros and ones as inputs;• produce zeros and ones as outputs.

inputs outputs

Integrated Circuits

0

1

0

1

0

1

0

1

circuit

1

0

Why do we want this? • zeros and ones represent information;• circuit performs computation.

inputs outputs

Integrated Circuits

0

1

0

1

0

1

0

1

circuit

1

0

How do we build (design) such circuits? • hierarchically, from components.

inputs outputs

All (or mostly) About “Bits”

0 1

zero one

false true

off on

open closed

not asserted asserted

not set set… …

Truth Tables

Example

8 rows3 variables

4 rows2 variables

2m rowsm variables

264 rows64 variables

1 1 1 1

0000111

0011001

0101010

0001010

x1 x2 x3 f

One made-up fact…

[well, an abstraction really…]

A Logic Gate

1x

2x

dx

di

ix

,,1allfor

{0,1}

{0,1}{0,1}: dg

),,( 1 dxxg

“AND” gate

0001

Common Gate:

1x

2x

g0011

0101

1x 2x g

Logic Gates

“OR” gate

0011

0101

0111

Common Gate:

1x

2x

g

1x 2x g

Logic Gates

“NAND” gate

0011

0101

1110

Common Gate:

1x 2x g

Logic Gates

1x

2x

g

“NOR” gate

0011

0101

1000

Common Gate:

1x 2x g

Logic Gates

1x

2x

g

“XOR” gate

0011

0101

0110

Common Gate:

1x

2x

g

1x 2x g

Logic Gates

Linear Threshold Gates

1x

2x

nx

1w

2w

nw

0w... ),,( 1 nxxf x

ni

ix

,,1allfor

{0,1}

0if1

0if0

2210

2210

nn

nn

xwxwwxw

xwxwwxwf

w

ni

iw

,,0allfor

R

Linear Threshold Gates

Useful Model?

),,( 11 mxxf a

),,( 12 mxxf a

),,( 1 mn xxf a

inputs outputs

Digital Circuit

1x

2x

mx

circuit

),,( 1 mn xxf a

),,( 11 mxxf a

),,( 12 mxxf a),,( 1 mxxf a

inputs outputs

1x

2x

mx

circuit gate

Digital Circuit

1x

2x

3x

4x

5x

6x

NAND

OR

ANDAND

AND

NOR

1

0

0

1

1

1

1

0

1

0

0

1

Digital Circuit

Data Structures

Example

Truth Tables

1 1 1 1

0000111

0011001

0101010

0001010

x1 x2 x3 f

x1

x2

x3

f

Sequential Circuits

clock

synchronous, finite number of states

inputs

),,( 1 nxxX

outputs

),,( 1 mzzZ

memoryelements

),,( 1 kyyY

combinationalcircuit

A Computing System…

“A person's mental activities are entirely due to the behavior of nerve cells, glial cells, and the atoms, ions, and molecules that make them up and influence them.”

– Francis Crick, 1982

Astonishing Hypothesis

“That the astonishing hypothesis is astonishing.”

– Christophe Koch, 1995

The Astonishing Part:

Domains of Expertise

• Vision• Language• Abstract Reasoning• Farming

Human

Circuit

• Number Crunching

• Mining Data• Iterative

Calculations

Artificial Life

US Patent 20070122826 (pending):“The present invention relates to a minimal set of protein-coding genes which provides the information required for replication of a free-living organism in a rich bacterial culture medium.” – J. Craig Venter Institute

Going from reading genetic codes to writing them.

Artificial Life

Going from reading genetic codes to writing them.

Moderator: “Some people have accused you of playing God.”

J. Craig Venter:“Oh no, we’re not playing.

Biochemistry in a Nutshell

DNA: string of n nucleotides (n ≈ 109)

... ACCGTTGAATGACG...

},,{},,,{ 2013 aaGTCA

Nucleotides:

Amino acid: coded by a sequence of 3 nucleotides.

Proteins: produced from a sequence of m amino

acids (m ≈ 103) called a “gene”.

},,,{ GTCA

protein},,{ 201 maa

Biochemical Reactions: how types of molecules combine.

+ +2a b c

Playing by the Rules

Biochemical Reactions

9

6

7

cellproteins count

+

8

5

9

Discrete chemical kinetics; spatial homogeneity.

Biochemical Reactions

+

+

+

slow

medium

fast

Relative rates or (reaction propensities):

Discrete chemical kinetics; spatial homogeneity.

Protein-ProteinChemistry

[computational] Biochemistry

y

x

quantities

z

Biochemical [computation]

quantity

Multiplication

pseudo-codebiochemical code

Exponentiation

biochemical code

pseudo-code

Raising-to-a-Power

pseudo-code

biochemical code

Language as a Window into the way the Brain Works

Steven Pinker, Harvard

Circuits & Computers as a Window into our Linguistic Brains

CircuitBrainConceives of circuits and

computation by “applying” language.

Lousy at all the tasks that the brain that

designed it is good at (including language).

?