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Submission + - Free Pascal Compiler 3.0.0 is out, adds support for 16 bit MS-DOS and 64 bit iOS ( 1

Halo1 writes: Twenty-three years ago, development started on the first version of the Turbo Pascal and later also Delphi-compatible Free Pascal Compiler, for OS/2 no less. Two decades and change later, the new Free Pascal Compiler 3.0.0 release still supports OS/2, along with a host of older and newer platforms ranging from MS-DOS on an 8086 to the latest Linux and iOS running on AArch64. On the language front, the new features include support for type helpers, codepage-aware strings and a utility to automatically generate JNI bridges for Pascal code. In the mean time, development on the next versions continues, with support for generic functions, an optional LLVM code generator backend and full support for ISO and Extended Pascal progressing well.

Submission + - Raspberry Pi Zero $5 Computer (

mikejuk writes: Rumours that something new was coming from the Raspberry Pi team have proved true — a $5 computer the Raspberry Pi Zero is here to give the BBC micro:bit and other low cost devices some competition.
The new Pi Zero offers quite a lot of hardware for $5:
A Broadcom BCM2835 application processor
1GHz ARM11 core (40% faster than Raspberry Pi 1)
A micro-SD card slot
A mini-HDMI socket for 1080p60 video output
Micro-USB sockets for data and power
An unpopulated 40-pin GPIO header
Identical pinout to Model A+/B+/2B
An unpopulated composite video header
form factor 65mm x 30mm x 5mm
1x Micro USB Data port
comes with Micro USB ‘On the Go’ adapter and Mini HDMI to HDMI adapter
It also runs Raspbian including Scratch, Minecraft and Sonic Pi. The GPIO is the same as all of the previous Pis but it doesn't come with a 40-pin connector soldered into place — so some assembly is required if you want to use it as an microcontroller. The same is true if you want to make use of the composite video output to drive older display devices.
To emphasize how low cost this device is, it is being given away free with this month's MagPi, the magazine published by the Raspberry Pi Foundation, which claims, probably correctly, that this is the first time a computer has been given away as a covermount.
This really is a revolution — disposable computing is here

Comment Another useful vacuum tube: Thermionic converter. (Score 1) 93

Another vacuum tube technology with current applications and substantial advantages over semiconductor approaches to the same problems is the Thermionic Converter. This is a vacuum-tube technology heat engine that turns temperature differences into electric power - by boiling electrons off a hot electrode and collecting them, at a somewhat more negative voltage (like 0.5 to 1 volt), at a cooler electrode.

Semiconductor approaches such as the Peltier Cell tend to be limited in operating temperature due to the materials involved, and lose a major fraction of the available power to non-power-producing heat conduction from the hot to the cold side of the device. Thermionic converters, by contrast are vacuum devices, and inherently insulating (with the heat conducted almost entirely by the working electrons, where it is doing the generation, or parasitic infrared radiation, which can be reflected rater than absorbed at the cold side.) They work very well at temperatures of a couple thousand degrees, a good match to combustion, point-focused solar, and nuclear thermal sources.

Thermionic converters have been the subject to recent improvements, such as graphine electrodes. The power density limitation of space charge has been solved, by using a "control grid" to encourage to charge to move along from the emitter to the collector and magnetic fields to guide it (so it doesn't discharge the control grid and waste the power used to charge it).

Current thermionic technology can convert better than 30% of the available thermal energy to electrical power and achieves power densities in the ballpark of a kilowatt per 100 square cm (i.e. a disk about 4 1/2 inches in diameter). That's a reasonably respectable carnot engine. This makes it very useful for things like topping cycles in steam plants: You run it with the flame against the hot side so it is at the combustion temperature, and the "cold" side at the temperature of the superheated steam for your steam cycle. Rather than wasting the energy of that temperature drop (as you would with a pure steam cycle) you collect about a third of it as electricity.

It also beats the efficiency of currently available solar cell technology (and the 33.4% Shockleyâ"Queisser theoretical limit for single-junction cells), if you don't mind mounting it on a sun-tracker. Not only that, but you can capture the "waste heat" at a useful temperature without substantial impairment to the electrical generation or heat collection, and thus use the same surface area for both generation and solar heating. (Doing this with semiconductor solar cells doesn't work well, because they become far less efficient when running a couple tens of degrees above room temparature.)

Submission + - Raspberry Pi unveils new $5 mini-computer

An anonymous reader writes: The Raspberry Pi Foundation unveiled the Pi Zero, a new $5 mini-computer, Thursday morning. The board is the smallest Raspberry Pi yet, containing the first-gen Raspberry Pi's BCM2835 chip (safely overclocked to 1GHz) and 512MB RAM. The latest issue of The Magpi will include a free Raspberry Pi Zero and hits U.K. newsstands Thursday. The announcement came just a few days before the highly anticipated C.H.I.P. $9 mini-computer goes on sale to the public.

Comment Re:Duh (Score 1) 561

I think you missed the simple fact that everything was working fine before, without cramming everything in the init process.

Has everything been crammed into the init process? In what may have been a bad PR move, the systemd people use "systemd" both to refer to the init process and to their whole suite of daemons, most of which run as processes separate from process 1, so "systemd does XXX" doesn't necessarily mean "XXX has been crammed into the init process".

Comment Re:Many a young engineer.... (Score 2) 93

... every schematic drawn by every semiconductor engineer got the arrow backwards.

As I heard it, The arrow is "backward" because Benjamin Franklin, when doing his work unifying "vitreous" and "resinous" electricity as surplus and deficit of a single charge carrier (and identifying the "electrical pressure" later named "voltage"), took a guess at which corresponded to a surplus of a movable charge carrier. He had a 50% chance to assign "positive" to the TYPICAL moving charge carrier in the situations being experimented with (charge transfer by friction between different substances, currents in metallic conductors, and high voltage discharges in air and water-in-air aerosols) and happened to guess "wrong".

Thus we say electrons have a negative charge, "classical current" corresponds to the sum of the flow of moving positive charge minus the flow of negative charge (i.e. the negative of the electron current, which is all there is in normal-matter metallic conductors), the arrowhead on diodes (and junction transistors) points in the direction of classical current across a junction, and so on.

But though it's the charge carrier in metallic conduction and (hard) vacuum tubes, the electron ISN'T the only charge carrier. Even in the above list of phenomena, positive ion flow is a substantial part of electrical discharge currents in air - static sparks and lightning. Positive moving charge carriers are substantial contributors to current as you get to other plasma phenomena and technologies - gas-filled "vacuum" tubes (such as thyratons), gas an LIQUID filled "vacuum" tubes (ignatrons), gas discharge lighting, arc lighting, arc welding, prototype nuclear fusion reactors, ...

Move on to electrochemistry and ALL the charge carriers are ions - atoms or molecular groups with an unequal electron and proton count, and thus a net charge - which may be either positive or negative (and you're usually working wit a mix of both).

And then there's semiconductors, where you have both electrons and "holes" participating in metallic conduction. Yes, you can argue that hole propagation is actually electron movement. But holes act like a coherent physical entity in SO many ways that it's easier to treat them as charge carriers in their own right, with their own properties, than to drill down to the electron hops that underlie them. For starters, they're the only entity in "hole current" that maintains a long-term association with the movement of a bit of charge - any given electron is only involved in a single hop, while the hole exists from its creation (by an electron being ejected from a place in the semiconductor that an electron should be, by doping or excitation, leaving a hole) to their destruction (by a free electron falling into them and releasing the energy of electron-hole-pair separation). They move around - like a charge carrier with a very short (like usually just to the next atom of the solid material) mean free path.

For me the big tell is that they participate in the Hall Effect just as if they were a positive charge carrier being deflected by a magnetic field. The hall voltage tells you the difference between the fraction of the current carried by electrons excited into a conduction band and that carried by holes - whether you think of them as actual moving positive charge carriers or a coordinated hopping phenomenon among electrons that are still in a lower energy state. Further, much of interesting semiconductor behavior is mediated by whether electrons or holes are the "majority carrier" in a given region - exactly what the hall effect tells you about it.

So, as with many engineering phenomena, the sign for charge and current is arbitrary, and there are both real and virtual current carriers with positive charge. Saying "they got it wrong" when classical current is the reverse of electron current is just metallic/thermionic conduction chauvinism. B

Comment Re:If we're going systemd, we should go full throt (Score 1) 561

Except when it doesn't and since it swallows stderr

A sane background/daemon process launcher sends stdout and stderr somewhere where it gets logged. Are you saying systemd just sends the standard output and error of stuff it launches to /dev/null, or that it sends them somewhere that's not easy to process? (Launchd sends them to the Apple System Log mechanism, which, yes, does have a binary log database, but ASL also sends stuff, including the stdout/stderr from launchd-launched processes, to the Boring Old Text File /var/log/system.log.)

Comment Re:If we're going systemd, we should go full throt (Score 1) 561

If as a result the Linux community grows closer together and focuses more on consistency I'm all for the move to systemd - even if that moves Linux away from the rest of the unixes due to loss of posix compliance.

Not that systemd affects POSIX compliance (and not that Linux is certified as POSIX-compliant; I haven't found it to be significantly worse than any other UN*X in terms of "annoyingly different from everybody else" - frankly, if there isn't at least one thing your UN*X-family OS does annoyingly differently from all the other UN*X-family OSes, it can't really call itself a UN*X :-)).

Comment Re:Vacuum tubes handle EMP's better (Score 1) 93

"No point progressing since the bombs are gonna fall any day now. Then where will your fancy silicon highways and databases be?"

Given that the Internet Protocol and much of the rest of the networking technology that still underpins the Internet were developed as part of a cold-war program to create a communication system that could survive a nuclear attack that destroyed most of it, and still reorganize itself to pass messages quickly, efficiently, and automatically among any nodes that still had SOME path between them, your post seems to come from some alternate universe to the one I inhabit.

Comment Re:Private companies don't do exploration of front (Score 1) 286

And their colony failed. The Spanish, Portuguese, English and French colonies in the New World succeeded because the governments that ran those colonies backed them financially and militarily. At least in the case of the English, owners/shareholders of colonials often received economic monopolies, giving them substantial impetus to make colonies economically viable in fairly short order.

And even though colonies could obviously become self-sustaining in pretty short order, they still required a significant amount of protection from the colonial power, and the colonial powers served as the route to accessing markets.

The Vikings experiments in colonization as private endeavors were mixed successes at best, and ultimately only Iceland survived as a successful colonial enterprise by the early Modern era, with the North American and Greenland colonies failing (though the Greenland colony did manage to hang on for several centuries).

There are probably any number of reasons; less than hospitable sites for colonization that were vulnerable to climactic changes at the top, but also the more limited means of making such colonies economically viable. At least in the North American attempts, the native peoples may have played a roll as well. The Norse simply didn't have the resources at their disposal that the Colonial Powers could bring to bear when they started seizing the New World. The Norse were hardly better equipped than the Inuit and Native Americans they encountered, whereas the Spaniards, French and English had firearms and much larger numbers.

Comment Re:The dark matter between their ears (Score 1) 150

But no one says it doesn't exist locally. Quite the opposite, everyone thinks it does. It's just fucking hard to see.

It's not that cosmologists aren't willing to look at GR, and certainly are, but no potential quantum theory of gravity suggests an alternative to dark matter. And considering we all know there is physics beyond the Standard Model, and the potential for currently only hypothetical or even unpredicted particles, the idea that we should just toss out one of the most successful scientific theories in history because we're confronted with what looks like a lot of extra mass seems absurd.

But I get it. There is a certain type of person, underachievers mainly, whose only contribution to any discussion is to find the gaps in our knowledge and then proclaim researchers in those fields retards. It's pathetic, and contributes absolutely nothing.

Comment Space-based Economy (Score 1) 286

In the very long run, probably. But I think there's probably a route to increasing space exploration and utilization by explicitly avoiding the cost of Earth-to-orbit transport costs. The plan I've seen that has some promise goes as follows:

1. Find some metal-rich and volatiles-rich asteroids and comets (not exactly rare in the Asteroid Belt). Tow these asteroids into a near-Earth orbit and begin extraction and smelting.
2. Set up manufacturing facilities in Earth orbit to build spacecraft and satellites.
2a. We could even "grow" plastics with bacteria or genetically-engineered plants.
3 ....
4. Profit!

In all seriousness, if you created a parallel space-based economy whose sole purpose is to make transporting anything but humans into space, then the whole question of how to make Earth-to-orbit transport cheaper ceases to be an issue. Obviously the startup costs and R&D for such a project are monumental, but in the long run, the rewards would be huge. The whole point of commercial spaceflight is to find a way to make it economically feasible, and this is about actually creating a space-based economy.

Hotels are tired of getting ripped off. I checked into a hotel and they had towels from my house. -- Mark Guido