PDP11 and Computer History"

The Legend lives ...

DEC PDP-11, benchmark for the first 16/32 bit generation.

1960: A young hardware engineer named Ben Gurley was hired to design DIGITAL's first computer. Three and a half months later, the prototype Programmed Data Processor-1 (PDP-1) was complete. In December, the prototype was demonstrated at the Eastern Joint Computer Conference in Boston.
From a technical bulletin on the PDP-1, dated March 1960: "...a compact, solid state general purpose computer with an internal instruction execution rate of 100,000 to 200,000 operations per second. PDP-1 is a single address, single construction, stored program machine with a word length of 18-bits operating in parallel on 1's complement binary numbers.

1970:
PDP-8 Specifications
Word Length: 12 Bits
Speed: 1.5 micro- second cycle time
Primary memory: 4K 12-bit word core memory
Secondary memory: 32K maximum
Instruction set: 3-bit op code, 1 indirect bit; 8 bits of address
Input/Output: teletype (ASR-33) includes paper-tape reader and punch
Power: 780 watts
Price: $18,000

1971: The PDP-11/45 was an excellent computational tool for large multi-user, multi-task installations. Through memory management, memory could be expanded to 128K, which included a combination of bi-polar and MOS memory. Other features included a greatly expanded floating point processor.

1975: The PDP-11/70 represented the high end of PDP-11 architecture with the capacity for supporting the speed, addressing range and bandwidth required in large systems applications. It was the first PDP-11 to use cache memory.

The midrange PDP-11/34 was DIGITAL's most successful PDP-11 in terms of unit volume. The 11/34 featured a CPU so compact that the entire CPU logic was contained on two circuit boards. This provided greater flexiblity during later system expansion by making additional chassis space available.

1977: The PDP-11/60 offered a combination of unique attributes, which were normally found in larger, more expensive computers at the time. Designed around the proven UNIBUS architecture, the PDP-11/60 included user control store features previously unavailable from DIGITAL as well as several 11/70 class features such as cache memory and RAMP.

1979: The PDP-11/44 incorporated the complete PDP-11/70 instruction set and memory expansion into 1MB in a lower-cost package. The PDP-11/44 was the last PDP-11 implemented in discrete logic.

1981: The PDP-11/24 was a fourth generation PDP-11 system designed to increase DIGITAL's penetration of the Technical and Commercial OEM markets. The new machine featured Large Scale Integration, 1 MB memory capacity and the PDP-11 UNIBUS.

1985: Key features of the MicroPDP-11/83, included the new high-performance central processing module (the KDJ11-BF) and a Private Memory Interconnect (PMI) Bus.

1990: Both the MicroPDP-11/93 and the PDP-11/94 offered a performance increase of up to 40% over the previous high-end PDP-11 systems. The new machines were the latest members of the longest-lived family of general-purpose computers. At this point, the series included over 20 members; more than 600,000 had been installed.

History of Computers

300 before Chr.: The Romans transform the abacus to the handy abacus.
In Europe these computing aids in the Middle Ages were used, in Eastern Asia, Russia and India are today still common them.

1617: Lord John Napier of Merchiston (1550-1610) designs so-called computing sticks, which enable also multiplications.
For the further relief of counting the logarithms and the logarithmic slide rule are introduced.

1622: After already so-called " logarithmic boards " were created, the mathematician William Oughtred (1574-1660) develops, today the still used slide rule with two logarithmic scales.

1623: William Schickard (1552-1635) designs a calculating machine driven by gear wheels.

1642: In Paris the mathematician Blaise Pascal presents a calculating machine, which is appropriate for eight-digit additions and subtractions and an automatic decimal carry has.

1673: The German universal scholar Freiherr Gottfried William of Leibniz (1646-1716) builds a machine for all four basic operations of arithmetic.
Leibniz develops the binary number system and formulates the regularities of binary arithmetic.

1805: The first machine, which is controlled by punch cards - templates with holes determined places completely on -, is the mechanical loom of the Frenchman Joseph Marie Jacquard (1752-1834). Already 1812 are more than 10,000 of these program controlled looms in the use.

1833: The English mathematician Charles Babbage (1792-1871) begins with the building of a digital computer.
The analytic computer should become program controlled with punch cards.

1886: Hermann Hollerith designs an electromagnetic sorting and counting machine for the analysis of punch cards.

1936:The British mathematician Alan Turing publishes a discussion of theoretically unsolvable problems. Therein it describes an apparatus, which it calls universal machine, and which the characteristics of a modern computer possesses.

1936: The German civil engineer Konrad Zuse (geb. 1910) builds a purely mechanical computer - Zuse Z1. He finished it in 1938.

1941: Konrad Zuse designs the first program controlled computer on behalf of the German laboratory for aviation. The Z3 is an electromagnetic computer, which contains about 2000 relays.
He operates with dual numbers and uses for the representation of numbers the floating point notation.
For a multiplication it needs three seconds of compute time.

1944: In Boston the mathematician Howard H. Aiken (1900-1973) finishs his work on his program controlled computer Mark of I.

1944: John von Neumann (1903-1957) begins with the conception of the computer EDVAC (electronics Discrete variable AUTOMATIC computer).
The machine can be put only 1952 into operation.
Only by the transition to flexible and internally stored programs the prerequisites for the modern data processing are justified.

Manchester Automat

1945: Zuse puts its Z4 into operation. It had a higher arithmetic performance than its predecessor and contains a punched-tape reader to the input of subroutines and a magnetic core memory.

1946: John P. Eckert (1919) and John W. Mauchly (1907 - 1980) develop the first all-electronic large computer installation of the world in Pennsylvania in the USA. For the first time instead of the relays the substantially faster electron tubes were used. The ENIAC (electronics Numerical integrator and Calculator) extended over a surface of 140 square meters and was equipped with more than 18,000 electron tubes. Programming was made not by means of punch cards but by a large quantity of lines and plugs on an instrument panel. 50 coworkers had worked three years on it.

1948: Three scientists at Bell Telephone Laboratories file for a patent on the first transistor.
In 1956 The Nobel Prize in physics is awarded to John Bardeen, Walter Brattain, and William Shockley for their work on the transistor.

1951: Howard H. Aiken finishs his work on its first computer Mark of III built with electron tubes.
It consists of approximately 2000 relays and 5500 electron tubes and 1300 diodes and uses a magnetic tape for the input of the program and the data.

1955: With the introduction of the transistor the so-called second computer generation begins.
On 19 March into the Bell Laboratories under the direction of J. H. Felker finishes the work on the first computer operating with the new logic elements.
The computer Tradic (transistor digitally computers), built by the US Air Force, consists of approximately 800 transistors and 11,000 germanium diodes.

1956: MIT researchers built the TX-0, the first general-purpose, programmable computer built with transistors.

1959: IBM's 7000 series mainframes were the company's first transistorized computers.

1960: The precursor to the minicomputer, DEC's PDP-1 sold for $120,000.

1965: Digital Equipment Corp. introduced the PDP-8, the first commercially successful minicomputer.

1969: Intel announces a 1 KB RAM chip, which has a significantly larger capacity than any previously produced memory chip.
Bill Gates and Paul Allen, calling themselves the "Lakeside Programming Group" sign an agreement with Computer Center Corporation to report bugs in PDP-10 software, in exchange for computer time.
Unix is developed at AT&T's Bell Laboratories.

1972: 5.25 inch diskettes first appear.
The DEC PDP-11 was the most popular in the PDP (Programmed Data Processors) line of minicomputers, a successor to the previously popular PDP-8 (the PDP-10 (1967) was a higher capacity 36-bit mainframe-like version of the PDP-8, much adored and rumoured to have souls), and remained in production until the decision to discontinue the line as of September 30, 1997

1973: Gary Kildall writes a simple operating system in his PL/M language. He calls it CP/M (Control Program/Monitor or Control Program for Microcomputer)
Bob Metcalfe invents the Ethernet connectivity system.

1975: In February Bill Gates and Paul Allen license their newly written BASIC to MITS, their first customer.
This is the first computer language program written for a personal computer.
In April Bill Gates and Paul Allen found Micro-Soft (the hyphen is later dropped).

1976: Steve Wozniak and Steve Jobs finish work on a computer circuit board, that they call the Apple I computer.

1977: Apple Computer moves from Jobs' garage to an office in Cupertino.
Bill Gates and Paul Allen sign a partnership agreement to officially create the Microsoft company.

1978: Intel begins production of the 8086 microprocessor. It is created by two engineers in just three weeks. Work on the processor began when it was realized that the i432 project was in trouble.

Digital Equipment opens a retail store in a shopping mall, for selling small computer systems priced below US$10,000.
The DEC VAX has been implemented as a microprocessor.The VAX architecture wasn't designed as a microprocessor, though single chip versions were implemented (around 1984). However, it and its predecessor, the PDP-11, helped inspire design of the Motorola 68000, Zilog Z8000, and particularly the National Semiconductor 32xxx series CPUs.
The VAX was a 32 bit architecture, with a 32 bit address range.

1979: Zilog ships samples of the 16-bit Z8000 processor.
Intel introduces the 4.77-MHz 8088 microprocessor. It was created as a stepping stone to the 8086, as it operates on 16 bits internally, but supports an 8-bit data bus, to use existing 8-bit device-controlling chips. It contains 29,000 transistors, using 3-micron technology, and can address 1MB of memory. Speed is 0.33 MIPS. A later version operates at 8-MHz, for a speed of 0.75 MIPS.

1980: Microsoft decides to propose to IBM that they provide the operating system for IBM's microcomputer.

1981: IBM announces the IBM 5150 PC Personal Computer, in New York. The PC features a 4.77-MHz Intel 8088 CPU, 64KB RAM, 40KB ROM, one 5.25-inch floppy drive (160KB capacity), and PC-DOS 1.0 (Microsoft's MS-DOS), for about US$3000. IBM announces the CGA graphics card for the PC, giving 640x200 resolution with 16 colors.

1992: The DEC Alpha architecture is designed, according to DEC, for a operational life of 25 years. The first Alpha chip is the 21064.
Alpha is a 64 bit architecture (32 bit instructions) that doesn't support 8- or 16-bit operations, but allows conversions, so no functionality is lost.
One of Alpha's roles is to replace DEC's two prior architectures - the MIPS-based workstations and VAX minicomputers.


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