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Fascinating read - Ted Hoff is a true engineer's engineer. I hadn't heard of him.
Misleading title when the content says things like.

"Federico Faggin was assigned to design the chip, and in nine months came up with working prototypes"... "Faggin recalled that when he began implementing the microprocessor, Hoff seemed to have lost interest in the project, and rarely interacted with him."

Kind of having a title like: "How Steve Jobs invented the first commercial personal computer" and then inside the article saying actually "Steve Wozniak designed the motherboard, power supply, video interface...."

For me this is the key quote:

> Hoff never even considered patenting the microprocessor. To him the invention seemed to be obvious.

I agree with him. The microprocessor wasn’t really an invention - it was a ‘technical milestone’. Once other techniques had been mastered then it was obvious it would happen.

Credit to Hoff for spotting that a single chip CPU would work in this case but that was really about being in the right place at the right time.

On the other hand Faggin did contribute some real inventions that made the 4004 possible and actually built the thing!

Yes, even the transistor was a logical consequence of existing work. The real breakthrough was the junction diode.
Ted Hoff worked in Atari Corporate Research (before Atari broke up / was purchased in 1984). This story was told to me by a friend who worked in ACR:

Ted had a pad of conductive foam with a number of 8008 processors (a few dozen, perhaps). From time to time he would be contacted by someone in the US government asking if he had any of those chips around.

He would pick one out, carefully package it and mail it off. Since the applications were almost always very secret, he never found out what they were actually for.

(These days, you'd just write a cycle and pin accurate emulator, or design an FPGA equivalent. Not an option back then).

Better still, if you're using Arduino, you just choose a different target processor from the pull-down menu, recompile, and off you go.

Of course I'm over-simplifying, but in fact, the portability of Arduino code across platforms has saved my bacon a few times during the chip shortage. There's always some overhead, such as changing a wiring harness, but it's better than being dead in the water.

Yeah, the clock speed of an 8008 (200Khz to 800Khz) was such that you could probably do a software emulation on just about any modern microcontroller and get all the pin timings correct.

I don't have a good sense if you succeed at pin-emulating a 1980s-era Z-80 or equivalent.

Why store CPUs in conductive foam? How is it better than something non-conductive?
it prevents any voltage potential from happening across the chip. if you touch an IC where every pin is floating you could damage the chip because of electrical discharge creating a voltage difference between different parts of a chip. if the difference is enough, current will flow whether it was given a path or it must create its own path.

if all pins are held at the same electrical potential, as they would be if stuck into conductive foam, touching the same chip brings up the voltage on all pins simultaneously (or close enough) so there will be no voltage differential across the chip and thus no arcing across the silicon. no damage.

ICs of the time almost never had built-in protection for this kind of thing. modern consumer computer components like RAM sticks for example, do. it's hard to damage those with static electricity shocks even if you try.

Yeah, some chips had ESD protection, a lot of the early ones did not. You treated bare chips with care, used an ESD mat when working with boards, grounded yourself with a wrist strap, and were realllly careful in non-lab spaces (where there were usually carpets, waiting to pounce). Still zapped stuff. Ugh.

I still have a habit of touching likely grounds from time to time whenever I'm in a lab.

> I still have a habit of touching likely grounds from time to time whenever I'm in a lab.

Me too, it's such an ingrained habit. Before touching any "open electronics", I quickly touch the earth lug on my lab PSU, or a screw from some other (grounded) metal test equipment case. I've been doing it so long and so consistently that my hands feel "wrong" before I do that.

So much stuff has ESD protection nowadays, but some individual components at least still don't, and you only need to break one part to ruin your day (or at least some significant amount of time if you're so lucky that you can solder a replacement).

Likewise here. With the back of my hand, another old habit.

Chips are more robust today, but not 100%, and some specialized devices like laser diodes are super sensitive to ESD.

The most evil thing are those plastic mats that people put over carpet in their offices so they can roll their rolling chairs. That's like sitting on a van de graaf generator. I killed several valuable EPROMs at my first job out of school, sitting at my desk, programming, then went to touch a chip to program it, ZAP!

When chips are in circuit boards, they're much less sensitive, due to the capacitance of the board traces. It's been a long time since I worried about handling a board. Of course the cost and irreplaceability of the board figures into the risk calculation.

Some say that the short answer is that Masatoshi Shima gave him the logical design and then visited California to browbeat him into actually getting the chip working. For some reason he's not mentioned by name in this article.
And this article bubbles up on the day Intel lays off 20k