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Comment Re:Was the Dynabook patented? (Score 2) 159

A very detailed article about the Dynabook was published in 1972:


The PDF makes it sound like an internal Xerox PARC report but it was actually article 1 in ACM '72 Proceedings of the ACM annual conference - Volume 1.

While previous patents are the first thing the US Patent Office looks for in prior art that might invalidate a patent under consideration, an article such as the above counts just as much. A public demonstration of a product would count too. In fact, even if the prior art was produced by the author of the patent it can invalidate it, though there is a grace period (six months or something like that) in the case of the patent's author. I don't know if that has changed in the move from "first to invent" to "first to file" by the USPO.

Once thing that always makes these discussions more confusing than they should be is that there are patents for inventions (how it works) and also patents for designs (how it looks). They are different and how they are invalidated by prior are is different. Since the summary talks about "rounded corners" and stuff like that we might be talking about a design patent.

Comment Smalltalk-80 instead of Squeak (Score 1) 414

Listing Squeak, which is one of the many available implementations of the Smalltalk-80 language, is pretty odd when all other entries are generic languages. So we have Basic instead of BBC Basic or GW Basic.

And when you list Smalltalk implementations, Squeak is more on the full featured side like VisualWorks than on the toy side like Little Smalltalk.

Comment Re:Embedded Systems (Score 1) 641

This. Half of the newer high-level languages today are just the mental masturbations of someone who either thinks he can make the wheel more round or the result of a "not invented here" mindset. There's so much crap out there forking a perfectly good language because someone thinks it should be a =+ b; instead of a += b;

You might not be aware that in very early versions of C the syntax was actually a=+b; but they changed that when they noticed there were two ways to interpret a=-1; and they decided they didn't want to use white space to distinguish between them.

Comment Re:cause and effect (Score 1) 786

Obviously I was generalizing. I am glad that your own experience wasn't like what I was saying. And it varies by culture quite a bit. In the 1980s I sometimes had the opportunity to show children computers for the first time when they visited my house with their parents for some reason. This was a pretty small sample, but I did notice the adults pushing the boys more than the girls even in the cases where the girl showed more interest.

Given that I was designing computers for children (first with Logo, later with Smalltalk) at the time, I was paying a lot more attention to this kind of thing than I normally would.

Comment cause and effect (Score 1) 786

The ads showed computers as toys for boys because that was what the market was like and not the other way around.

In the mainframe days most people only met a computers in their college days. Some would become more interested in them than what they were supposed to be studying (physics, biology, whatever - computer science courses were pretty rare back then) and would end up becoming programmers. It was mostly men, but there were a reasonable number of women (a lot more than today in relative terms, fewer in absolute numbers).

The microcomputer revolution happened because a certain kind of guy (as far as I know, no women participated in the Homebrew Computer Club meetings, for example) wanted to have his very own computer even if it was completely useless. Normal computer people looked down on those weirdos, but they soon hit it big. As prices came down it was possible to give a kid a computer as a toy. Practically no girls were interested (and those that were tended to be discouraged by parents and friends) but most boys were also not excited about calculating Fibanacci sequences or typing in Basic listings to draw mazes. It was a rather specialized market and that is what the ads aimed for.

The computers in the 1980s ads simply were not interesting for the general public. This changed in the early 1990s with the home office - a computer with disks and a reasonable printer and compatible with the one you had at work and changed yet again in the late 1990s with the Internet. That brought its own set of problems (which the Raspberry Pi was created to address) without killing the "computers are toys for boys" image that had been created.

Comment Re:Half a century (Score 1) 113

I used a B5500, at UC Santa Cruz, in a summer course on computer architecture in 1975, taught by one of its designers. Burroughs donated the obsolete machine, and we stepped it through instructions from its maintenance panel, watching the stack hardware work. We were also taken up to Xerox PARC to meet Alan Kay and see the original prototype Alto machines, years before Steve Jobs did. (They were really Data General Nova machines inside, with different microcode.)

The Altos were not too Nova-like, but the built-in part of their microcode did implement the Nova instruction set (except that the I/O instructions were used for other stuff). Alan had been previously using Novas in his projects (Smalltalk-72 was first implemented in Nova BASIC and then assembly, for example) and this allowed him to quickly port to the Alto.

Comment forgot rule 12 of evil overlords (Score 4, Funny) 196

I guess their team of advisors is incomplete:


"12. One of my advisors will be an average five-year-old child. Any flaws in my plan that he is able to spot will be corrected before implementation."


"60. My five-year-old child advisor will also be asked to decipher any code I am thinking of using. If he breaks the code in under 30 seconds, it will not be used. Note: this also applies to passwords."

Perhaps Microsoft doesn't consider itself evil? Lots of people no longer do. At least they followed rule 32 in this case.

Comment Re:Jetpacks, flying cars - same problme (Score 1) 127

Fluids "love" to twist, so laminar flows (such as the curtain of air along the inner surface of air amplifiers) don't always get the best results. The laminar flows seem so quiet and smooth so it is hard for our intuition not to consider them to be the way to move mass with the least energy.

Vortices can scale very well. I always point to the Red Spot on Jupiter as an example. Can one be generated on a scale that could keep a car or a person suspended in mid air while using less fuel than a helicopter? I think it is possible, but haven't proved it yet.

Comment Re:Jetpacks, flying cars - same problme (Score 1) 127

Stubby lifting bodies can be practical at interesting cruise speeds, but you wouldn't want to take off or land at such speeds. Adding VTOL capability would solve that problem, but then we are back to the big and slow propellers issue you explained so well. I believe it is possible to convert a small, low thrust, high speed jet to a high thrust, low speed one with no moving parts. Air amplifiers actually increase thrust below 5cm in diameter but reduce it for larger sizes, so you have to figure out why it doesn't scale and fix that. The Dyson fan (http://www.dyson.com/Fans-and-heaters/cooling-fans.aspx), for example, is a terrible jet engine.

Comment failed to learn from history (Score 1) 285

One of the issues that led to Brazil's "reserved market" policy (1977 to 1992: no foreign companies could make mini and microcomputers and there were no imports) was that in 1974 the government got so tired of US spying (including on companies such as Petrobras) that they set up a task force to create a cryptographic system for Telex machines (to be expanded to voice later).

Comment Re:It was all about cost (Score 1) 99

Some small corrections:

Data General Nova machines were popular at Xerox PARC before the Alto was developed, so one of the various instruction sets that the Alto supported was that of the Nova allowing old software to be easily ported to the new machine. Other than that, there was no relation between Xerox and Data General.

While the Alto and its successors (including the Star and specially the Dorado) were very expensive, there was the Notetaker project that would have had a huge impact if it had been released. Imagine a $3000 machine in 1979 like the future Compaq portable but with a mouse and GUI. Don't pay attention to what the Wikipedia or the Computer History Museum say about the machine, by the way, but look at the original documents instead:


The original plan was to create a Xerox microprocessor compatible with the Alto and use two 8086 for I/O. Imagine how cool that would have been! But the group was forbidden to do their own chips, though there was a division of PARC for doing just that. So the design was changed to three 8086s instead. And as neat as this was, there were plans for a cost reduced Notetaker 2. An executive flew from the east coast specially to kill the project and make sure it really died because the board had decided to keep Xerox outside of the silly microcomputer business. They changed their minds a little later and gave us a Z80 CP/M machine after IBM came out with their PC.

The only good thing about this was that the Notetaker's designer, Douglas Fairbairn, was so upset over the cancellation that he left PARC and founded VLSI Technology Inc. (VTI) which made possible for small companies to design their own chips. Like Acorn and their ARM.

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