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How Relevant is C in 2014?

Jecel Assumpcao Jr Re:Embedded Systems (641 comments)

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.

about 2 months ago

NPR: '80s Ads Are Responsible For the Lack of Women Coders

Jecel Assumpcao Jr Re:cause and effect (786 comments)

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.

about 3 months ago

NPR: '80s Ads Are Responsible For the Lack of Women Coders

Jecel Assumpcao Jr cause and effect (786 comments)

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.

about 3 months ago

Prof. Andy Tanenbaum Retires From Vrije University

Jecel Assumpcao Jr Amoeba (136 comments)

Interesting that he doesn't list Amoeba among his achievements. I find it far more impressive than Minix.

about 7 months ago

Unisys Phasing Out Decades-Old Mainframe Processor For x86

Jecel Assumpcao Jr Re:Half a century (113 comments)

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.

about 7 months ago

Bunnie Huang Shows Off His Open Source Laptop (Video)

Jecel Assumpcao Jr Re:I don't get it. (24 comments)

The original PC was fully open, but the AT had a keyboard controller and two PALs that had to be reverse engineered to produce a clone.

about 8 months ago

Five-Year-Old Uncovers Xbox One Login Flaw

Jecel Assumpcao Jr forgot rule 12 of evil overlords (196 comments)

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.

about 10 months ago

The Ephemerality and Reality of the Jetpack

Jecel Assumpcao Jr Re:Jetpacks, flying cars - same problme (127 comments)

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.

about a year ago

The Ephemerality and Reality of the Jetpack

Jecel Assumpcao Jr Re:Jetpacks, flying cars - same problme (127 comments)

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.

about a year ago

Brazil Announces Plans To Move Away From US-Centric Internet

Jecel Assumpcao Jr failed to learn from history (285 comments)

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).

about a year ago

Why Are Fantasy World Accents British?

Jecel Assumpcao Jr Re:Now think in American. (516 comments)

I thought King Arthur was Celtic (speaking Latin with a Celtic accent) and fought against the Anglo Saxon invaders. And that Robin Hood spoke French, so English would be fake for him no matter what accent is used (not that the movie goers would ever accept this).

more than 2 years ago

Reinventing Xerox PARC As a Money Maker

Jecel Assumpcao Jr Re:It was all about cost (99 comments)

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.

more than 3 years ago

Wikipedia Losing Contributors, Says Wales

Jecel Assumpcao Jr banned for life for using real name (533 comments)

I find it ironic that several people are proposing that demanding real names would solve some of Wikipedia's problems because I was banned for life for using a "spam user name", which happens to be my real first name (I have never used a nickname since I got online in 1986, except in systems that use numbers as user IDs). Now I know that is not the real reason, but it is the official reason and the only option they offer for getting my account unbanned is to post a special message selecting a different user ID, which then wouldn't be my real name.

My guess is that the real reason I was banned was because my home page (which was deleted) only had a short phrase about me and a link to my home page, which is a company page. When I created my account (a few years before the guy who banned me), I took a quick look at a few other user pages and most were like this so I just copied their style. If this is not acceptable, then just delete the page. I don't care: I was asked to create a page when I created the account though I didn't really want to. But banning for life seems a bit harsh.


more than 3 years ago

Futureproofing Artifacts: Spacewar! 1962 In HTML5

Jecel Assumpcao Jr Re:Asteroids (175 comments)

That's a *basic* system; the point-plotting CRT display used in Spacewar! would have added quite a bit to the cost.

Is this correct? I always had the impression that the display was a standard part of the PDP-1 and only became optional in later models.

more than 3 years ago

Computer Industry Mourns DEC Founder Ken Olsen

Jecel Assumpcao Jr Re:DEC scared IBM in the 80's (172 comments)

For DEC they could have gone downscale to PCs, but the profit margins are too low: it's a commodity item. IBM doesn't build PCs anymore; they sold their PC business to Lenovo.

People, including Gordon Bell, like to mention Ken's "Nobody needs a computer in their home" quote to say he lacked the vision to get into the PC market. I don't agree - as much as it saddens me, the home computer was a fad that had died out by the 1990s. People have PCs, which is a business machine, in their home offices.

While DEC's PC efforts failed, this 1982 movie shows that they did try:


This approach, trying to leverage their PDP-11 and PDP-8 technologies, had a better chance of working than their later industry standard stuff, like the Rainbow. But I think they were about three years too late.

more than 3 years ago

EDSAC Computer To Be Rebuilt

Jecel Assumpcao Jr Re:first computer with stored programs? (97 comments)

None of the early Zuse machines were stored program computers - they had a relay memory for data and got their instructions from punched tape. The table in the Wikipedia page about the Z3 seems about right:


The Manchester Baby was the first stored program machine, quickly followed by the modified ENIAC (the original used patch panels and cables) and then the EDSAC. Since the Baby was created to explore ideas for the EDSAC rather than as a usable machine on its own, I guess if you squint enough the article is right in an Obi-wan kind of way :-)

about 4 years ago

BSG Prequel Series Caprica Canceled

Jecel Assumpcao Jr Re:Was BSG's ending really so bad? (602 comments)

Can you imagine an episode with Admiral Adama addressing the United Nations? How could that not suck?

Why don't you search for "UN BSG" on Youtube and see what it would look like? :-)

more than 4 years ago

Internet Archive Puts 1.6M E-Books On OLPC Laptops

Jecel Assumpcao Jr Re:XO Design question (106 comments)

The official reason why the ARM wasn't used was that none of the many available models had decent floating point when the OLPC project was started. Unfortunately, the Geode's floating point performance turned out to be less than what was hoped. Unofficially, I imagine that the fact that AMD was one of the four initial sponsors of the OLPC biased the choice towards their product, just like having Red Hat as one of the other sponsors led to the Fedora based software (in contrast to using some already stripped down Linux distribution).

Things have changed since 2005, including the decision by AMD to discontinue the Geode (which they had bought from National, who had bought the creator Cyrix). The decision to use the x86 compatible Via processors for the XO 1.5 greatly reduced the software effort, which is very important given their current limited staff.

I am a huge fan of the ARM (I think I was the first one in the world outside of Acorn itself to use this processor in a project) but back in 2005 my suggestion for OLPC was that they should do their own custom chip using two Leon 3 (Sparc) cores. I still think it would have been a good idea.

more than 5 years ago


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