Intel Releases 4004 Microprocessor Schematics

mcpublic writes, "Intel is celebrating the 35th anniversary of the Intel 4004, their very first microprocessor, by releasing the chip's schematics, maskworks, and users manual. This historic revelation was championed by Tim McNerney, who designed the Intel Museum's newest interactive exhibit. Opening on November 15th, the exhibit will feature a fully functional, 130x scale replica of the 4004 microprocessor running the very first software written for the 4004. To create a giant Busicom 141-PF calculator for the museum, 'digital archaeologists' first had to reverse-engineer the 4004 schematics and the Busicom software. Their re-drawn and verified schematics plus an animated 4004 simulator written in Java are available at the team's unofficial 4004 web site. Digital copies of the original Intel engineering documents are available by request from the Intel Corporate Archives. Intel first announced their 2,300-transistor 'micro-programmable computer on a chip' in Electronic News on November 15, 1971, proclaiming 'a new era of integrated electronics.' Who would have guessed how right they would prove to be?"

Comments

a bit of relevant info....

[frakir]

pasted from http://www.cpu-world.com/CPUs/4004/index.html> :

The first microprocessor in history, Intel 4004 was a 4-bit CPU designed for usage in calculators, or, as we say now, designed for "embedded applications". Clocked at 740 KHz, the 4004 executed up to 92,000 single word instructions per second, could access 4 KB of program memory and 640 bytes of RAM. Although the Intel 4004 was perfect fit for calculators and similar applications it was not very suitable for microcomputer use due to its somewhat limited architecture. The 4004 lacked interrupt support, had only 3-level deep stack, and used complicated method of accessing the RAM. Some of these shortcomings were fixed in the 4004 successor - Intel 4040.

Re:Fast-forward

[Mitchell Mebane]

ISA, as in "Instruction Set Architecture". Not the bus.

Re:how about minix ?

[TheRaven64]

It couldn't run Minix, and it would be quite hard to port Minix to it. It already runs on 8086 CPUs, so it doesn't need an MMU (or an FPU). Originally it came with 40-bytes of RAM, which is certainly not enough for Minix. It supports 12-bit addressing though, so you can address 4K-words. Unfortunately, the word size is 4-bits, so that means you can only address 2KB of RAM, which is definitely not enough for Minix. For reference, Bash is about 284 times bigger than the entire address space of the 4004. If you tied it with a custom MMU chip, you could possibly extend this to 4096 segments of 4096 words, giving you 8MB of total address space. This would be enough for Minix, but you'd need to do a lot of paging, which would slow down the performance of the 4004 chip a lot. It would probably boot in under a week...

Re:More Relevant Info?

[turly]

Dunno what you're smoking, fella, but Motorola never "got" the 6502. From this article:

The 6502 was designed primarily by the same engineering team that had designed the Motorola 6800. After quitting Motorola en masse, they quickly designed the 6501, a completely new processor that was pin-compatible with the 6800 (that is, it could be plugged into motherboards designed for the Motorola processor, although its instruction set was different). Motorola sued immediately, and MOS agreed to stop producing the 6501 and went back to the drawing board.

The result was the "lawsuit-compatible" 6502, which was by design unusable in a 6800 motherboard; Motorola dropped their objection.
...
The 6502 was introduced at $25 in September 1975, when the 6800 and Intel 8080 were selling for $179. At first many people thought the new chip's price was a hoax or a mistake, but shortly both Motorola and Intel had dropped their chips to $79. Far from the intended result, these price reductions actually legitimized the 6502, which started selling by the hundreds.

Re:Railroad gauges

[Cadallin]

I really rather disagree with their conclusion. Although it was not "inevitable" the fact of the matter is that the rail road gauge that became dominant in the USA and Europe CAN be traced to the one adapted for rail use from carriages designed to fit on roads built to a standard specified originally by the Roman Legions based on the width of the asses of two standard war horses. That this is merely coincidental doesn't make it any less true, or less telling about the nature of beaurocracy and resistance to change. And the fact of the matter is that the standard does continue to affect rail shipping to this day, as it most definately determines what an oversize rail car or load is. Whether or not this actually had a direct impact on the Space Shuttle's SSRB's is less clear, although certainly they had to be designed so that they could be shipped from the factory to Cape Canaveral.

The thrust of the point to me, is the very point that nobody sat around and actually considered what might be a good rail gauge to adopt for shipping lines, they just went ahead with a horribly odd standard that was already in existence.

Re:Railroad gauges

[johnw]

The thrust of the point to me, is the very point that nobody sat around and actually considered what might be a good rail gauge to adopt for shipping lines

One man did. Isambard Kingdom Brunel did exactly that. He sat down and thought about what gauge to make his railway (The Great Western) and came up with 7 feet as a much more sensible value. He was entirely correct, but unfortunately his version was abandoned simply because far more people had used the existing default.

John