IBM 700/7000 Series

Overview

• Type: Mainframe/scientific computer
• Release Date: 1953
• Successor: IBM 8000 (not released), IBM System/360
• Related Series: IBM 1400 series, History of IBM mainframes (1952-present)
• Market Name: Includes 700/7000 series, 1400 series, System/360, System/370, and others up to IBM Z.

Architecture

• IBM 700/7000 Series:
  • Large mainframe systems from the 1950s and early 1960s.
  • Variety of incompatible processor architectures.
  • 700s use vacuum-tube logic, 7000s are transistorized.
  • Replaced by System/360 in 1964, though some 7000s remained in use due to early OS/360 issues.

Architectures

• Six Different Architectures:
  • First Scientific (36/18-bit words): IBM 701 (Defense Calculator)
  • Later Scientific (36-bit words): Models like 704, 709, 7090, 7094, etc.
  • Commercial (Variable-length character strings): 702, 705, 7080
  • 1400 Series (Variable-length character strings): 7010
  • Decimal (10-digit words): 7070, 7072, 7074
  • Supercomputer (64-bit words): 7030 "Stretch"

Software Compatibility Issues

• Early computers lacked software.
• Multiple architectures required different programming efforts.
• System/360 aimed to unify 7000 and 1400 series into one design but wasn't fully compatible.
• System/370 improved emulation capabilities.

Peripherals

• Tape Drives: 7-track format (IBM 727 for vacuum tube, 729 for transistor machines)
• Common Peripherals: Card readers (IBM 711), Card punches (IBM 721), Line printers (IBM 716)
• Faster Peripheral Operations: Often performed off-line using IBM 1401
• Adopted Midline Peripherals: Machines like the 7010, 7040, and 7044 used peripherals from the IBM 1400 series.

Scientific Architecture (701)

• IBM 701:
  • Known as Defense Calculator, unveiled April 7, 1953.
  • Data Formats: 36 or 18-bit long numbers (fixed point)
  • Instruction Format: 18 bits long
  • Registers: 38-bit Accumulator (AC), 36-bit Multiplier-Quotient (MQ)
  • Memory: 2,048 or 4,096 36-bit binary words

Later Scientific Architecture (704/709/7090/7094)

• Used for computation-intensive applications.
• Data Formats: 36-bit numbers for fixed-point and floating-point arithmetic
• Registers: 38-bit AC, 36-bit MQ, 15-bit Index Registers (three or seven), 36-bit SI
• Memory: Ranges from 4,096 to 32,768 36-bit binary words

Commercial Architecture (702/705/7080)

• IBM 702 and 705:
  • Similar architecture; 705 is backward compatible with 702.
• IBM 7080: Transistorized version of 705
• Data Format: Variable-length character strings
• Registers: Varied across models
• Memory: Ranges up to 160,000 characters

1400 Series Architecture (7010)

• Inspired IBM 1400 series business computers.
• Data Format: Variable length strings terminated by a word mark

Decimal Architecture (7070/7072/7074)

• Decimal, fixed-word length machines.
• Data Format: 10 decimal digits plus sign
• Registers: 99 index registers

Timeline

• Key dates and models from 1952 to 1964, showcasing transitions in technology (e.g., vacuum tubes to transistors).

Performance

• Predates modern benchmarks, but some models are noted for speed or computing time in specific tasks.

Key Notes

• IBM's 700/7000 series laid important groundwork for future mainframe systems.
• Transition from vacuum tubes to transistors marked a significant technological advancement.
• Compatibility issues were a significant challenge, leading to the development of more unified systems like System/360.

See Also

• IBM 650
• IBM 705, 7030 Stretch, 7070, 7094
• IBM 7090/94 Architecture

References

• Reference materials on IBM systems and architecture evolution.