CS计算机代考程序代写 ada Lecture 2 – Historical Perspective

Lecture 2 – Historical Perspective

Stewart Smith Digital Systems Design 4

Digital System Design 4
Lecture 2 – An Historical

Perspective

Dr Stewart Smith
& Dr Chang Liu

Stewart Smith Digital Systems Design 4

This Lecture

• Events leading up to the development of
the stored program computer.

Stewart Smith Digital Systems Design 4

Computing Before Computers –
W. Aspray

• A textbook on computing technology prior to the
development of the first electronic stored-program
computer – look for it on Learn. In this lecture we
follow the same outline.
‣ Early Calculation
‣ Difference and Analytical Engines
‣ Analog Computing Devices
‣ Logic Machines
‣ Punched-Card Machinery
‣ Relay Calculators
‣ Electronic Calculators
‣ Stored Program Computers (Additional)

Stewart Smith Digital Systems Design 4

Early Calculation
• Counting
‣ e.g. Sheep

• Pictorial Representation
‣ e.g. Pictures of sheep, pebble representation

• Counting Rods, Roman Numerals (MDCXVI)

http://en.wikipedia.org/wiki/Counting_rods

0 1 2 3 4 5 6 7 8 9

Vertical

Horizontal

http://en.wikipedia.org/wiki/Counting_rods
http://en.wikipedia.org/wiki/Counting_rods

Stewart Smith Digital Systems Design 4

Early Calculation

• Old Roman numerals
‣ 3,745 would be represented as MMMDCCXXXXV
‣ M=1000, D=500, C=100, L=50, X=10, V=5, I=1
‣ Addition:

2319 = MM CCC X V IIII

+821 = D CCC XX I

3140 = MM D CCC CCC XXX V IIIII

= MMM C XXXX
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

Stewart Smith Digital Systems Design 4

Early Calculation
• Old Roman numerals
‣ M=1000, D=500, C=100, L=50, X=10, V=5, I=1
‣ Multiplication:

28 = XX V III

⇥12 = X II

336
AAACNHicdVDLSgMxFM3UV62vqks3waK4sUxanwuh4MbipoKtA51SMmmmDc08SDJCGTr/5MYPcSOCC0Xc+g1m6ghV9MKFwzn3cs89TsiZVKb5ZORmZufmF/KLhaXlldW14vpGSwaRILRJAh4Iy8GScubTpmKKUysUFHsOpzfO8DzVb26pkCzwr9UopB0P933mMoKVprrFy8oJ3D2DtofVQLqxZSWtpF6vj227YCvmUQlRZXogSawkk0l6M0b7lXGhWj3STLdYMsvmpOAUODTR6RGCKGNKIKtGt/hg9wISedRXhGMp28gMVSfGQjHC6bhgR5KGmAxxn7Y19LH204knT4/hjmZ60A2Ebl/BCTu9EWNPypHn6MmJ999aSv6ltSPlnnRi5oeRoj75OuRGHKoApgnCHhOUKD7SABPBtFdIBlhgonTOaQjfn8L/QatSRmYZXR2UarUsjjzYAttgDyBwDGrgAjRAExBwBx7BC3g17o1n4814/xrNGdnOJvhRxscnPtSoKA==AAACNHicdVDLSgMxFM3UV62vqks3waK4sUxanwuh4MbipoKtA51SMmmmDc08SDJCGTr/5MYPcSOCC0Xc+g1m6ghV9MKFwzn3cs89TsiZVKb5ZORmZufmF/KLhaXlldW14vpGSwaRILRJAh4Iy8GScubTpmKKUysUFHsOpzfO8DzVb26pkCzwr9UopB0P933mMoKVprrFy8oJ3D2DtofVQLqxZSWtpF6vj227YCvmUQlRZXogSawkk0l6M0b7lXGhWj3STLdYMsvmpOAUODTR6RGCKGNKIKtGt/hg9wISedRXhGMp28gMVSfGQjHC6bhgR5KGmAxxn7Y19LH204knT4/hjmZ60A2Ebl/BCTu9EWNPypHn6MmJ999aSv6ltSPlnnRi5oeRoj75OuRGHKoApgnCHhOUKD7SABPBtFdIBlhgonTOaQjfn8L/QatSRmYZXR2UarUsjjzYAttgDyBwDGrgAjRAExBwBx7BC3g17o1n4814/xrNGdnOJvhRxscnPtSoKA==AAACNHicdVDLSgMxFM3UV62vqks3waK4sUxanwuh4MbipoKtA51SMmmmDc08SDJCGTr/5MYPcSOCC0Xc+g1m6ghV9MKFwzn3cs89TsiZVKb5ZORmZufmF/KLhaXlldW14vpGSwaRILRJAh4Iy8GScubTpmKKUysUFHsOpzfO8DzVb26pkCzwr9UopB0P933mMoKVprrFy8oJ3D2DtofVQLqxZSWtpF6vj227YCvmUQlRZXogSawkk0l6M0b7lXGhWj3STLdYMsvmpOAUODTR6RGCKGNKIKtGt/hg9wISedRXhGMp28gMVSfGQjHC6bhgR5KGmAxxn7Y19LH204knT4/hjmZ60A2Ebl/BCTu9EWNPypHn6MmJ999aSv6ltSPlnnRi5oeRoj75OuRGHKoApgnCHhOUKD7SABPBtFdIBlhgonTOaQjfn8L/QatSRmYZXR2UarUsjjzYAttgDyBwDGrgAjRAExBwBx7BC3g17o1n4814/xrNGdnOJvhRxscnPtSoKA==AAACNHicdVDLSgMxFM3UV62vqks3waK4sUxanwuh4MbipoKtA51SMmmmDc08SDJCGTr/5MYPcSOCC0Xc+g1m6ghV9MKFwzn3cs89TsiZVKb5ZORmZufmF/KLhaXlldW14vpGSwaRILRJAh4Iy8GScubTpmKKUysUFHsOpzfO8DzVb26pkCzwr9UopB0P933mMoKVprrFy8oJ3D2DtofVQLqxZSWtpF6vj227YCvmUQlRZXogSawkk0l6M0b7lXGhWj3STLdYMsvmpOAUODTR6RGCKGNKIKtGt/hg9wISedRXhGMp28gMVSfGQjHC6bhgR5KGmAxxn7Y19LH204knT4/hjmZ60A2Ebl/BCTu9EWNPypHn6MmJ999aSv6ltSPlnnRi5oeRoj75OuRGHKoApgnCHhOUKD7SABPBtFdIBlhgonTOaQjfn8L/QatSRmYZXR2UarUsjjzYAttgDyBwDGrgAjRAExBwBx7BC3g17o1n4814/xrNGdnOJvhRxscnPtSoKA==

XX V III⇥ I = XX V III
XX V III⇥ I = XX V III
XX V III⇥ X = CC L XXX

= CC L XXXXXXX VV IIIIII

= CCC XXX VI
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

Stewart Smith Digital Systems Design 4

Early Calculation
• The Abacus
‣ Roman

‣ Chinese Suanpan
MM CM XM M C X I Ө

Ө = 1/12 (uncia)

1-5

5/10

6,302,715,408

Stewart Smith Digital Systems Design 4

Early Calculation

• Carries and Precision
‣ Japanese Soroban
‣ 27 digit number representation

http://sonuprince.wordpress.com/2009/12/
http://www.tertisco-alexandru.com/abacus_project.html

http://sonuprince.wordpress.com/2009/12/
http://www.tertisco-alexandru.com/abacus_project.html

Stewart Smith Digital Systems Design 4

Early Calculation
• European Table Abacus
‣ 287,452

W.Aspray – Computing before computers
A page from Robert Recorde’s book on arithmetic – 1542

Stewart Smith Digital Systems Design 4

Early Calculation

John Napier
1550-1617

Stewart Smith Digital Systems Design 4

Early Calculation

3105×6 = 18630

Stewart Smith Digital Systems Design 4

Early Calculation
Mechanical Calculators

Stewart Smith Digital Systems Design 4

Early Calculation
Henri Genaille & Edouard Lucas, Genaille-Lucas Rulers – 1885

Stewart Smith Digital Systems Design 4

Early Calculation
Henri Genaille & Edouard Lucas, Genaille-Lucas Rulers – 1885

Stewart Smith Digital Systems Design 4

Early Calculation
• Logarithms

• Mirifici Logarithmorum Canonis Descriptio – 1614
• Henry Briggs
‣ “Napier, lord of Markinston, hath set my head and hands at

work with his new and admirable logarithms. I hope to see him
this summer, if it please God; for I never saw a book which
pleased me better, and made me more wonder.”

‣ Published a book containing tables of the logs from 1 to
20,000 and from 90,000 to 100,000 all calculated to 14
decimal places.

‣ There are 1161 errors in these original tables, or just under
0.04 percent of the entries

Natural numbers 1 2 4 8 16 32 64 128 256 512 1024
Logarithm 0 1 2 3 4 5 6 7 8 9 10

Stewart Smith Digital Systems Design 4

Early Calculation
• In the 1600s there existed a vast network of computers that

communicated by packet switching.
• Computer:
‣ noun
‣ noun: computer; plural noun: computers
‣ 1. an electronic device which is capable of receiving information (data) in

a particular form and of performing a sequence of operations in
accordance with a predetermined but variable set of procedural
instructions (program) to produce a result in the form of information or
signals.

‣ 2. a person who makes calculations, especially with a calculating machine.
• Dutch printer, Adrian Vlacq (1600-1667) – published a table of

the first 100,000 logarithms, The errors propagated into almost all
log-tables.

Stewart Smith Digital Systems Design 4

Early Calculation
Wilhelm Schickard & Johann Kepler, 1617

http://history-computer.com/MechanicalCalculators/Pioneers/Schickard.html

A replica of the Schickard’s machine, created by
Bruno v. Freytag Löringhoff in 1960 (©

Universität Tübingen)

http://history-computer.com/MechanicalCalculators/Pioneers/Schickard.html

Stewart Smith Digital Systems Design 4

Early Calculation
William Oughtred (1574-1660)

http://web.mat.bham.ac.uk/C.J.Sangwin/Sliderules/oughtredquotes.html

Circles of Proportion and The
Horizontal Instrument

http://web.mat.bham.ac.uk/C.J.Sangwin/Sliderules/oughtredquotes.html

Stewart Smith Digital Systems Design 4

Early Calculation
James Watt (late 1700s) and Amadee Manheim (1850)

http://home.vicnet.net.au/~wolff/calculators/sliderules/sliderules.htm

The Slide Rule

http://home.vicnet.net.au/~wolff/calculators/sliderules/sliderules.htm

Stewart Smith Digital Systems Design 4

Early Calculation
Blaise Pascal – 1642

Pascal’s Calculating Machine
http://www.sciencemuseum.org.uk/images/i055/10323035.aspx

http://www.sciencemuseum.org.uk/images/i055/10323035.aspx

Stewart Smith Digital Systems Design 4

Early Calculation
Gottfried Wilhelm Leibniz (1646-1716)

The Stepped Drum The Liebniz Calculator

http://www.sciencemuseum.org.uk/images/i055/10323035.aspx

http://www.sciencemuseum.org.uk/images/i055/10323035.aspx

Stewart Smith Digital Systems Design 4

Early Calculation
• Successive Improvements to these devices (variable

toothed gears) continued to be used until ~1910

http://www.schneemann.de/ A Brunsviga Calculating Machine

http://www.schneemann.de/

Stewart Smith Digital Systems Design 4

Early Calculation
Curta Calculator – 1948

http://en.wikipedia.org/wiki/Curta

http://en.wikipedia.org/wiki/Curta
http://en.wikipedia.org/wiki/Curta

Stewart Smith Digital Systems Design 4

Difference and Analytical Engines
• Charles Babbage – 1791

• The Difference Engine

• T = x2+x+41

http://en.wikipedia.org/wiki/Difference_engine
Built in 1991

http://en.wikipedia.org/wiki/Difference_engine

Stewart Smith Digital Systems Design 4

Difference and Analytical Engines
• Charles Babbage & Ada Lovelace
• The Analytical Engine

Stewart Smith Digital Systems Design 4

Difference and Analytical Engines
• Charles Babbage & Ada Lovelace
• The Analytical Engine

Stewart Smith Digital Systems Design 4

Difference and Analytical Engines
The Jaquard Loom

http://en.wikipedia.org/wiki/Jacquard_loom

http://en.wikipedia.org/wiki/Jacquard_loom

Stewart Smith Digital Systems Design 4

Analog Computing Devices
• G Starke’s Planimeter (1849)
‣ Used for computing the area enclosed by a closed curve

http://www.yorku.ca/lbianchi/sts3700b/lecture20a.html

http://www.yorku.ca/lbianchi/sts3700b/lecture20a.html

Stewart Smith Digital Systems Design 4

Analog Computing Devices
Lord Kelvin’s Tide Predicting Device (1876)

http://en.wikipedia.org/wiki/Tide-predicting_machine

http://en.wikipedia.org/wiki/Tide-predicting_machine

Stewart Smith Digital Systems Design 4

Analog Computing Devices
Antikythera Mechanism

http://en.wikipedia.org/wiki/Antikythera_mechanism

Made in 87 BCE, found in 1901 CE

http://en.wikipedia.org/wiki/Antikythera_mechanism

Stewart Smith Digital Systems Design 4

Logic Machines
• Automata
• Classical Propositional Logic
• Claude Shannon – MIT, 1938
‣ True – Circuit Closed
‣ False – Circuit Open
‣ AND – Serial
‣ OR – Parallel

• Alan Turing – On Computable Numbers, 1937

Stewart Smith Digital Systems Design 4

Logic Machines
• Turing Machine – a logical/theoretical construct
• A mathematical function is only computable if

and only if it can be computed by the Universal
Turing Machine

Stewart Smith Digital Systems Design 4

Punched Card Machinery
• The Hollerith Machine
‣ 1890 US Census

• The Tabulating Machine Company
• International Business Machines -1924

http://en.wikipedia.org/wiki/Tabulating_machine

http://en.wikipedia.org/wiki/Tabulating_machine

Stewart Smith Digital Systems Design 4

Relay Calculators

• Electromagnetic
Relays

• Easy to implement
mechanical functions
electrically.

Stewart Smith Digital Systems Design 4

Relay Calculators
• Telephone networks in the 1930s used relays

and vacuum tubes.

• Konrad Zuse in Berlin, George Stibitz in New
York, and Howard Aiken in Cambridge,
Massachusetts, conceived and developed
calculating systems that exploited the relay’s
potential as a component of a computer.

• In the ~1940s Bell Labs used a Bi-quinary
system for encoding decimal digits.

Stewart Smith Digital Systems Design 4

Relay Calculators

• Zuse and Stibitz’ computers, e.g. Z1-4, Model-K,
Complex Number Computer, Model II–V defined the
architecture of the modern computer.

• Howard Aiken worked on automating an IBM calculator
to help him complete his dissertation in physics – the
Automatic Sequence Controlled Calculator

‣ Grace Hopper worked for Aiken at Harvard
‣ She found a moth that was stuck in a relay, causing the

calculator to malfunction & noted that she had found a “bug”.

Stewart Smith Digital Systems Design 4

Relay Calculators
• In the ~1940s Bell Labs used a Bi-quinary system for

encoding decimal digits.
• The principles from the Chinese abacus were used for

the first error correcting codes.
Decimal Bi-quinary

0 01-00001
1 01-00010
2 01-00100
3 01-01000
4 01-10000
5 10-00001
6 10-00010
7 10-00100
8 10-01000
9 10-10000

Stewart Smith Digital Systems Design 4

Relay Computer
https://www.youtube.com/watch?

v=n3wPBcmSb2U

Stewart Smith Digital Systems Design 4

Electronic Calculators
• Vacuum Tubes ~1930s, Cambridge, England.
‣ A digital or analog device.

• 1939, John Atanasoff, Iowa, Electronic
Calculator with “DRAM”

• 1942, Helmut Schreyer, Berlin, triodes as
binary relays

• 1943, Turing, Newman, Flowers, Bletchley,
The Colossus.

Stewart Smith Digital Systems Design 4

Development of The Electronic
Stored Program Computer

• The history of these developments in the 1940s to 1960s
is remarkable, and far, far, too much for one lecture.

• Historical perspective chapter 1.12 from textbook
• I suggest you read these books to get a complete picture.
‣ Turing’s Cathedral by George Dyson
‣ The Information by James Gleick

Stewart Smith Digital Systems Design 4

Development of The Electronic
Stored Program Computer

• The ENIAC (Electronic Numerical Integrator And Computer), 1945,
U.Penn
‣ John Mauchly
‣ Presper Eckert

• Manchester Small Scale Experimental Machine – 1948
‣ Frederic C. Williams
‣ Tom Kilburn
‣ Geoff Tootill

• EDVAC (Electronic Discrete Variable Automatic Computer) – 1949
‣ John Mauchly
‣ Presper Eckert
‣ Von Neumann

• IAS – 1952
‣ Turing
‣ Von Neumann

Stewart Smith Digital Systems Design 4

Preliminary Discussion of The Logical Design
of an Electronic Computing Instrument

• This paper is on Learn, I suggest you read
it just now and revisit it towards the end
of the course.

Stewart Smith Digital Systems Design 4

Moore’s Law

Stewart Smith Digital Systems Design 4

Next Lecture: Modern Technology
and Types of Computer

• Types of computing
‣ (§1.1 – Introduction)

• Software / Hardware Hierarchy
‣ (§1.2 – Below Your Programme)

• Parts of a computer
‣ (§1.3 – Under the Covers)