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11

IBM

• “business machines”- punch cards- electromechanical calculators

• slow introduction of electronic machines

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of Utah

22

IBM 701

• “Electronic Data Processing Machine”

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of Utah

33

IBM 701

• 2000 multiplications per second• Plastic tape, not metal

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of Utah

44

Memory

• Williams Tube- CRT for memory, not pictures!- 1024 bits

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of Utah

55

IBM 701

• Marketing- 1954 election prediction- English/Russian translation

• 19 systems installed!

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of Utah

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Sell or rent?

• IBM rented, not sold, their computers

• UNIVAC sold, not rented.

• Advantages?

• Disadvantages?

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of Utah

77

ERA

• Engineering Research Associates- Spinoff from Navy- Build drum memory

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of Utah

88

ERA

• Navy “Task 13”• Commercial “Model 1101”

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of Utah

99

ERA

• Ran out of money• Bought out by Remington Rand

- same people who bought UNIVAC!- Marketed 1103 for science- UNIVAC for business

conflict of interest?

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of Utah

1010

Drum memory

• Durable but slow- (picture on page 39)

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of Utah

1111

CRC

• Computer Research Company- “102A computer”

• Bought out by NCR

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1212

Notice a Pattern?

1.New company experiments with new technology

2.Runs out of money3.Bought by established company as easy

path to new business

This is not a new phenomenon!

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of Utah

1313

LGP-30

• Librascope/General Precision- famous drum computer- cheap ($30,000)- small (desk-size)

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of Utah

1414

Flexowriter

• Only I/O device for many computers

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of Utah

1515

Bendix G-15

• Another drum-based computer• Fast but difficult to program

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of Utah

1616

IBM 650

• IBM's drum machine• 1000 installed!• Discount price for universities

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of Utah

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IBM 650

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of Utah

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Computer sales

• BINAC: 1• UNIVAC: 46• IBM 701: 19• LGP-30: 400• Bendix G-15: 400• IBM 650: 1000

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of Utah

1919

How do you write a(non-infinite)

loop withouta break condition?

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of Utah

2020

2 Reminders and 1 Announcement

• Enigma homework due tonight at 7:30pm• ENIAC assignment due next Friday!• No school on Monday

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of Utah

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“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!)