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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."
The resulting compact enclosure had heat problems
... 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..
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.
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
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.
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.
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:
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/
If you specify it in computations performed per Watt of electricity consumed, Moore's law essentially ened or at least slowed considerably several years ago. The DEC Alpha made a big impression because the motherboard shipped with a heat sink on the CPU (the original "hot" CPU!). Used to be that a 230 Watt power supply was considered "server class". Now you can buy desktops with kilowatt power supplies.
Statesman
It's interesting how bean-counter thinking almost kept Intel from being the biggest chip company:
Article quote: Frassanito recalled accompanying Roche to a meeting with Bob Noyce, head of Intel, in early 1970 to try to get Intel -- then a start-up devoted to making memory chips -- to produce the CPU chip. Roche presented the proposed chip as a potentially revolutionary development and suggested that Intel develop the chip at its own expense and then sell it to all comers, including CTC, Frassanito recalled.
"Noyce [of Intel] said it was an intriguing idea, and that Intel could do it, but it would be a dumb move," said Frassanito. "He said that if you have a computer chip, you can only sell one chip per computer, while with memory [Intel's current focus], you can sell hundreds of chips per computer.
Table-ized A.I.
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.
I wish I could find a picture online of the interior of a MK8 Range Keeper or MK6 Stable Vertical - two elements of a fire control computer for an Iowa class battlewagon - imagine something larger than the desk that desktop PC sits on stuffed full of mechanical and electromechanical calculating equipment.
When they rebuilt the Iowas in the 1980's they kept the old analog equipment because a digital replacement would have been extremely expensive, and wouldn't have been any more accurate. The main limitation on their accuracy wasn't the computer, but the elevation and traversing drive equipment in the turrets.
The 8086 set the PC technology back 15 years, at least. At 1985, the Amiga could do hi-res multicolor bitmap displays, preemptive multitasking, hardware-accelerated graphics and sound, DMA, auto-configurable peripherals (through Zorro slots), 32-bit programming (although the addressing was 24 bit) without the curse of far pointers, and many other goodies that came much later in the PC world.
The PC technology was largely retarded: stupid BIOS, stupid VGA register layout, stupid memory addressing, stupid interrupt controller, stupid DMA...all these things were very hard to program. But it dominated the world, because of compatibility...