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Origins of the Modern PC

Homncruse writes "ComputerWorld dispels myths about the history of modern day computers — or, more appropriately, the invention of the first microprocessor. Contrary to popular belief, 'the [Intel] 8008 was not actually derived from the 4004 — they were separate projects.' In fact, the 8008 concept didn't originate from Intel (though they were eventually granted IP rights.) The article goes on to explain the events leading up to the invention and first intended use of the 8008 (a predecessor to the 8086, etc.), and how Intel was initially uneasy about the venture."

18 of 99 comments (clear)

  1. Curse? by BitterOldGUy · · Score: 4, Funny
    Roche died in a car accident in 1975, Ray died in 1987, and Noyce died in 1990. Frassanito left Datapoint to set up his own firm in 1975 and worked on the space shuttle and space station projects, among other things.

    Coincidence? I think not! There's some sort of curse going on with that computer and I predict that, sooner or later, everyone associated with that project will die!

    I know it's hard to believe, but I am clairvoyant.

  2. A TTL CPU still made for a "simple" machine. by jeffb+(2.718) · · Score: 5, Informative

    I enjoyed the Blueprint of the Datapoint 2200 enclosure, showing the crowded interior. I guess the caption writer has never seen the inside of a mechanical calculator. Imagine an object the size of a small desktop PC enclosure, entirely stuffed with mechanical linkages. It's truly astonishing.

    By comparison, a handful of circuit boards stuffed with SSI and MSI chips was delightfully simple. No moving parts! No lubrication! No wear!

    1. Re:A TTL CPU still made for a "simple" machine. by urcreepyneighbor · · Score: 5, Informative

      Imagine an object the size of a small desktop PC enclosure, entirely stuffed with mechanical linkages. It's truly astonishing.

      Linkage: Extreme example. Cool example.

      Sometimes, pictures are needed. :)

      --
      "The fight for freedom has only just begun." - Geert Wilders
    2. Re:A TTL CPU still made for a "simple" machine. by Anonymous Coward · · Score: 4, Interesting

      I have worked on the Datapoint 2200, when I was just starting out. A magnificent machine for it's time! It was multi-tasking two dual card reader punches, two daisy wheel printers, was master of a 16 node TTY local network and an SNA controller to boot! This was with a CPU that was, IIRC, mostly 8008 compatible ( plus a second register set al la Z80 ). a maximum load of 16Kb of RAM,
      two true digital cassette decks and a 12 x 80 screen. This was circa 1975 . All one had to do was keep the the dust off the chips and change the tape drive belts once a year and it ran for at least the 7 years I was around.

  3. Look at A/C systems by Chmcginn · · Score: 5, Insightful

    ... I can't believe they were having problems overclocking back then TOO. You'd think in 40 years, someone would have come up with a better solution that using water..

    Fossil fuel engines, refridgeration and air conditioning systems have been around a lot longer than that, and there's still no better way to cool off something hot than running a cool liquid around it.

    --
    Have you been touched by his noodly appendage?
  4. I refuse to read the article by Rik+Sweeney · · Score: 4, Funny

    I refuse to read the article because it goes against my creationist beliefs.

    How dare you suggest that the x86 evolved from the 8008. Me and my other enlightened brothers believe that the x86 was created by the supreme BG (MBWH*) who resides in MS, a utopia where all processors will eventually return to.

    *Megahertz Be With Him

  5. Tenuous connection by Ancient_Hacker · · Score: 5, Interesting

    Tracing the x86 back to the 8008 is a mighty tenuous connection.

    There are two very weak links.

    First, the 8008 to 8080 transition was a major re-do. Like ten times the speed, an external stack, more. The opcodes were upwardly compatible to a point, but that's about the only similarity.

    Next, the 8080 to 808x transition was just as abrupt. 16 bit registers, segments, and more. Again there was a certain backward compatibility, if you converted all the mnemonics and register names, but that was about all.

    1. Re:Tenuous connection by mysticgoat · · Score: 4, Informative

      Upwardly compatible opcodes was the overarching reason why, in that era, the 8086 was considered a true descendant of the 8080, and the 8080 was considered the true descendant of the 8008.

      Remember we are talking about an era when Assembly Language was the highest level of programming abstraction available on the early micro computers. The compilers that converted AL to binary machine language ran on minicomputers, were state of the art, expensive, hard to acquire, and difficult to use. Developing under these conditions, and attempting to fit working programs into 4, 8, or even a glorious 16 kilobytes of RAM, was an art form that no one has had to practice in more than 30 years.

      There was a tremendous advantage in developing a chip that allowed extension of the existing AL compilers without total rewriting, and allowed the AL programmers of the day to build upon their old skills. That some of the routines developed for the 8008 would also run on the 8086 / 8088 was a fringe benefit.

      Disclaimer: while I was writing my first "HELLO WORLD" programs in Fortran on punch cards at the time the 8008 was put on the market, my first PC was an Apple II+ (about 8 years later) and I learned 6502 Assembly rather than 8086 code. I have since managed to forget all those old skills. Good riddance! It is much better to scratch out new ideas in Perl, and then if there is some reason to optimize, get a code monkey or two to do the low level work.

    2. Re:Tenuous connection by dstates · · Score: 4, Informative

      The Z80 was an upwardly compatible extension/clone of the 8080A. The Z80 was designed by Federico Faggin at Zylog after he left Intel. Faggin had previously designed the 8080 when he was at Intel. So the Z80 is a derivative, not "in between" any of the Intel CPUs. Interestingly, Zylog licensed the Z80 design royalty free creating a robust second source market. Z80s dominated the 8-bit CPU market in the late 1970s.

      --
      Statesman
  6. Wang Labs by Sanat · · Score: 4, Interesting

    Wang (now a defunct company) built a PC in the early 70's that was actually called a "PC" but it stood for Professional Computer. It used the 8088 technology. Earlier prototypes utilized the 4004 and the 8008 as well and was in other technology designed by the company R&D department. Later the computer used the 8086 but for years was not "IBM" compatible at the microcode level thus could not run IBM type programs. The company was inflexible on fixing the problem as they expected IBM to conform to Wang Standards rather than vice versa. Some of the instruction set worked differently in order to save a clock cycle or two.

    Eventually the Wang PC became IBM compatible but it was too little... too late and the use of the PC was pretty much restricted to being a terminal rather than a full fledged processing device.

    Dr. An Wang was the person who designed core memory and started Wang Laboratories in the 50's. What an inspiration he was (and still is although he died in 1990) to young and old who are inspiring individuals with creative talents.

    --
    And in the end, the love you take is equal to the love you make
  7. Re:Overclocking in the 70s? by Kjella · · Score: 4, Interesting

    Well, energy doesn't just "go away" you can really only transport it elsewhere and to transfer heat away you need to have a medium to transport it with, even if it's just air. Plain old water has a very high specific heat - it takes more energy to heat water one degree than pretty much everything per except hydrogen gas per kilo, and in volume it can't really be matched. Airflow got less than 1/3000th the specific heat as the same volume of water flow. You can put a bottle of water and a solid copper lump the same size on a heater and the copper will heat up quicker.

    The other part is getting the heat out of the medium again - in a case with no airflow or a water cooling with no pump, it doesn't matter much how much energy it can store since it's never released. For my machines it's fine to just let it out into the room. In a server room, you need to get that heat out of the room too. Again there's really no magic to be made - you need a large surface area and a large temperature differential. That's why heatsinks have all the fins and fans blow cool intake air over them. A water cooling system can absorb a lot of it, but it too needs to get rid of it.

    In short, there's no easy way to solve the heat problem because it's down to basic physics. If you can find a way to make the heat just go away, you'll get the nobel prize in physics.

    --
    Live today, because you never know what tomorrow brings
  8. Word processors by Animats · · Score: 5, Interesting

    In the 1970s and early 1980s, before general-purpose personal computers, there was a whole industry for "word processors". These were special-purpose machines which offered text editing, printing, and storage for documents. They replaced typewriters. For the first time, people could edit documents without retyping. Word processors were not intended to be user-programmable; they ran a built-in application. Wang was a big name in that area, as were Datapoint and IBM. The original IBM PC reused the display from the IBM Displaywriter, IBM's family of word processors.

    The next step was "shared-logic word processors", where several terminals connected to a central unit, with the central unit having a disk and printer. This was a low-end version of time-sharing. Datapoint introduced ArcNet, so the word processors could send documents to each other. But none of this stuff was user-programmable, although the hardware underneath was a general purpose CPU. It wasn't considered reasonable that users in a typical office could program something as complex as a computer. Also, these machines barely had an operating system; they were usually running the application on the bare machine.

    After the IBM PC came out, Wang tried to enter that business. They weren't very successful. I used one of their early 8086 machines, the Wang PIC, which had a scanner. It ran a variant of DOS, which, interestingly, allowed about 800K of user space instead of 640K, because they did the split between RAM and device space at a higher address than IBM did. (The real 8086 limit isn't 640K; it's 1024K minus whatever address space is needed for devices.) It used a completely different (and more rugged) plug-in card design than the IBM PC, and wasn't software-compatible. A nice machine, it just lost out for being incompatible.

    So really, PCs are descended from these word processors.

    1. Re:Word processors by Amiga+Trombone · · Score: 4, Insightful

      I find it kind of sad that most people reading this have never typed on anything that doesn't rely on electrons to work.

      +1 Irrelevant Old Fart Comment

      +1 Get Off My Lawn Comment

      As somebody who's quite old enough to remember typing on things that didn't rely on electrons or even electricity, I can tell you for sure I don't miss the joys of carbon paper, having to start from scratch if you made a mistake, changing ribbons or unjamming jammed keys at all.

      That's like saying you feel sad because some people have never experienced the joy of taking a crap in an outhouse on a cold winter day.

      Sir, what are you thinking of?

    2. Re:Word processors by ratboy666 · · Score: 4, Interesting

      "Barely had an operating system" -- my ass.

      Take the Philips P2000/P5000 series.

      Yes, I wrote the OS and DOS. Some features:

      - 64KB of memory (yes, not megabytes, kilobytes)
      - possible bank switching (P5000) for 64KB additional memory
      - fully pre-emptive OS
      - didn't use "p/v semaphores", used event bits of synchronization
      - full interrupt support, able to handle floppy, keyboard, printer i/o and processing concurrently
      - could edit, print, and copy files at the same time.
      - two level directories on floppy (document/page structure)
      - automatic read-after-write checks and re-allocaton of bad blocks (floppy media expensive)

      Note that some of these features did NOT appear in common PC systems until 1995 (full preemption). Memory allocation used fixed length blocks -- we couldn't tolerate fragmentation.

      --
      Just another "Cubible(sic) Joe" 2 17 3061
  9. Re:Overclocking in the 70s? by orasio · · Score: 4, Insightful

    There are lots of better solutions.
    My favorite is to decrease wattage, it's just simpler.
    Passive heatsinks are good, too.
    Liquid cooling not involving water is used, too.

    The problem comes when you want to define "better".
    We have lots of engines that are better than the internal combustion engine, but in that case, "better" depends on so many things, that nobody agrees to choose a replacement.

  10. Pretty good connection for developers by lenski · · Score: 5, Interesting

    It was Intel's clear intention to allow simple, fully automatic translation of assembly code between one generation and the next. So the fact that the transition from each generation to the next is expressed in large steps does not make it a mighty tenuous connection. To exemplify:

    (1) The slow speed of the 8008 required hardware acceleration for parity computation, so the 8008 ALU provided a parity bit in the flags register. That bit lasted all the way through the Pentium line. (Could it remain in X86_64? I no longer work in the assembly language world and do not know.)

    (2) The original A,B,C,D,E,H/L register configuration with its byte/word weirdness in the 8008 was still plainly visible in the 16-bit X86 line, and hints of those structures lasted right through IA32, though IA32 does have significant improvements in orthogonality. (This is the genesis of the non-orthogonal register sets that compiler writers complained about all the way through IA32, which are fully rectified only with X86_64.)

    The connection is not only not tenuous, but (I claim, having worked with every CPU they built from the 8008 to my current Core2duo) clearly connected by an intentional, nearly unblemished record of source-level backward compatibility for the 40 years of its history.

    You do have a good point with respect to the way Intel scheduled its generational developments. When my group at AT&T was debating a project based on i486 DX2/66 and i960CA/CF, the Intel FAEs were exceptionally forthcoming with us about the way Intel developed their processor families. One of the more interesting things I learned was that Intel's X86 families were developed using dual teams, each team leapfrogging the other with successive generations. There was constant discussion among the teams, so often ideas from one would slip into the other.

    There is no question that each generation was intended to be as large a leap as possible beyond the last, so you do have a good point about the internal architecture of the processor families.

  11. Such great managers... by ericferris · · Score: 4, Interesting

    1. Hire enginners

    2. Do the opposite of what they recommend

    3. ????

    4. Errr... Where is the profit?

    Ye flippin' gods.

    Let me summarize a few salient points of TFA here:

    • CTC management refused to buy the IP rights of the microprocessor for a paltry 50K (about $300K in today's dollars), a ridiculously low sum as far as circuit design is concerned.
    • The same management (maybe not the same persons though) were then caught cooking the books after CTC became Datapoint

    It's very nice that the name of Roche was documented in this article for posterity. But what we really want is to have the name of these managers documented and written down in business textbook, along with their pictures, the history of their glorious achievements, and maybe a warning such as "Do not hire, consult, play golf with, or even breathe the same air as those morons".

    I'd call this a case of terminal stupidity, but this pun is way too refined for the monstrous cluster-f*ck that these PHBs achieved.

    --
    Fantasy: http://ferrisfantasy.blogspot.com/
  12. The second 8080 app by Anonymous Coward · · Score: 4, Informative

    or at least one of the first few, was also a PC - a Programmable Controller used for controlling industrial equipment or processes. Eagle Signal's Industrial Controls Division's CP700 Eptak modular system was 8080 based, and some of the early software was developed on Datapoint terminals. They paid $365 each for the first 8080s - an 8080A now goes for $1 or less. Eagle also ran what might have been the first college-level microprocessor course in-house for employees. It was taught by a prof from Iowa State and covered the 8080, 6800 and 6502. The original 8080s also required an external clock as the two pins across which you were supposed to be able to attach a crystal wouldn't osciallate. Don't recall the clock speed - 1MHz initially I think - but the 4MHz Z80 was considered a major speed advance.

    Eagle Signal also had a Traffic Control Division (you can still see their traffic light control cabinets on street corners) that was one of the first 8008 users, and also used Data General Novas for traffic controls.

    Neither Eagle Signal division exists any longer. Both were owned by Gulf+Western Industries in the early 70s and located in Davenport, IA. Both divisions eventually moved to Austin, TX. Danaher now owns the industrial controls product line, and probably makes more profit selling Eagle's HP5 electro-mechanical timers than its electronic products, which was where the company's profits always came from.