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Comment: Re:The local paper had this tidbit (Score 1) 812

That's happened to me. I have a Macbook Air; it's kinda sharp on the front. The person in the seat in front dropped their seat back really abruptly, with the result that I ended up getting guillotined in the gut by the edge of the laptop. It was painful.

I forget which airline it was --- possibly Swiss; I doubt it was Easyjet, as their seats don't recline.

Comment: Re:One of the most frustrating first-world problem (Score 1) 191

by david.given (#47666437) Attached to: Reversible Type-C USB Connector Ready For Production
You can actually get cables with a USB A connector on both ends. Yes, they're abominations of nature that make about less electrical sense than a mains cable with a plug on both ends, but you can actually buy them. They're typically only needed one some idiot who doesn't know what they're doing designs a piece of kit with the wrong socket. See, for example:

I have one right here on my desk. It connects a cheapo (but effective) battery charger to a USB power supply. The charger has an A socket, and it connects to a standard charger via an AA cable.

I keep meaning to superglue it into the charger to prevent someone connecting two of my computers together and something horrible happening.

Comment: Re:Solaris not well supported by OSS toolchain (Score 1) 183

Because this never works.

What happens instead is that people latch on to some irrelevant detail in your context and the discussion gets instantly derailed in that direction, thus ensuring that your question never gets answered. It's particularly fatal to mention motive, because that's completely subjective. The only way to actually get useful answers to questions these days is to trim the context as ruthlessly as you possibly can.

One day someone needs to write a "How To Answer Questions The Smart Way".

Comment: Re:Write your name with a pen? (Score 1) 82

I think that's the point.

I suspect the reasoning is that one physical copy == one license. By having the physical copy tied to you, by putting your name in it, they ensure you can't pass it on to anyone else, which means the license becomes non-transferrable. That means it's safe for them to give you a digital copy of the book, covered by the same license, in the knowledge that nobody else can claim a digital copy from the same physical book, without buying a new copy.

I would also be entirely unsurprised if each ebook was personalised, containing the image of your signature, so that if you gave a copy to someone else they'd know. I also see no mention of DRM (but the FAQ mentions using Calibre to convert ebooks, which suggests they don't use it).

Comment: Not actually sou (Score 5, Interesting) 77

The Videocore IV on the Raspberry Pi (which totally kicks arse, BTW, it's a beautiful, beautiful processor. Did you know it's dual core?) currently doesn't have an open source compiler that's any good[*] which I'm aware of. I have tried porting gcc, and got a reasonable way into it, but ground to a halt because gcc. I know another guy who's similarly about half-way through an LLVM port. And Volker Barthelmann's excellent vbcc compiler has a VC4 prototype which makes superb code, but that's not open source at all.

Without a compiler, obviously the source isn't much good, although the VC4-specific code is really interesting to look through.

In addition, having done a really brief scan of the docs they've released, this isn't what the article's implying: what we've got here looks like the architecture manual for the QPU and the 3D engine. The QPU is the shader engine. Don't get me wrong, this is awesome, and will allow people to do stuff like compile their own shaders and do an OpenCL port, but I haven't seen any documentation relating to the VideoCore IV processor. The binary blob everyone complains about runs on that.

It does looks like the source dump contains a huge pile of stuff for the VC4, so maybe they're going to release more later. But even incomplete, this is a great step forward, and much kudos to Broadcom for doing this.

[*] I have done a really crap port of the Amsterdam Compiler Kit compiler for the VC4. It generates terrible, terrible code, but I have got stuff running on the Raspberry Pi bare metal. It's all rather ground to a halt because there's still a lot of stuff to figure out in the boot process, but interested parties may wish to visit

Comment: Re:Watch out (Score 1) 99

by david.given (#45694459) Attached to: SpaceX Wins Use of NASA's Launch Pad 39A

Even better --- they've just demonstrated the ability to go to GEO, which is about 14km/s from the Earth's surface. Lunar orbit is only another 2.4km/s, and the moon's surface another 1.6 on top of that!

Chances are that with the technology they have right now, that is, using a modified F9 with the GEO upper stage, they could send a probe on a free-return trajectory to the moon. Or even easier, an impactor. I suspect they won't; Elon Musk appears to have his sights firmly set on the upgraded F9 Heavy and the rocket-landing Dragon, and with that setup you could probably remote land a complete Dragon capsule. I'd be really interested to know what sort of delta vee the Dragon's internal rockets will have...

Comment: Re:First (Score 5, Interesting) 250

by david.given (#45690649) Attached to: Chinese Lunar Probe Lands Successfully
As an interesting addendum:

Luna-9's pictures were sent back using one of the standard encodings used for wireless newspaper photography transmission. During the transmission, the Jodrell Bank radio telescope in the United Kingdom was listening in (well, wouldn't you?) and the astronomers there recognised the encoding, phoned someone at the Daily Express, and as a result the first pictures from the surface of the moon ever were printed in a British newspaper while the USSR was still wondering what to do with them.

There is some speculation that the encoding scheme was picked deliberately to make sure this happened...

Comment: Successfully landed (Score 5, Informative) 90

by david.given (#45688605) Attached to: Chang'e-3 Lunar Rover Landing Slated For 13:40 UTC Saturday
CCTV's live coverage showed a textbook landing and solar array deployment, including some very shiny live pictures from the descent imager. Next steps are self-testing, instrument deployment and releasing the rover, which they've said will take up to 24 hours. Although I'd imagine that they'll release images from the panoramic mast camera as soon as possible.

Comment: Re:Lets try to clear up some missinformation here (Score 4, Informative) 98

by david.given (#45525019) Attached to: Dual-Core Allwinner A20 Powered EOMA-68 Engineering Card Available

The RPi is an ARMv6, while this (along with pretty much every other modern ARM device) is an ARMv7. The ARMv6 has hardfloat but implements a slightly different version of the spec. Most OSes have standardised on the ARMv7 version which means that their code won't run on the ARMv6. So Debian armhf will run on this but will not run on the RPi: you have to use Raspbian instead, which is a version of Debian specifically compiled for the ARMv6. (Of course, Debian armel will run on both, but then you don't get any hardware floating point support.)

The Broadcom GPU is significantly awesome. It is, however, almost totally undocumented. There's a reverse engineering project which has mostly nailed down the instruction set, and there are even some C compilers for it (one of them is mine!) even though there's no gcc or LLVM support for it. You can write programs in C and run them on the bare metal. Unfortunately the GPU doesn't support double-precision float and the MMU is kinda weird, and it's probably going to be slower than the ARM for non-DSP-heavy code anyway, so it's unlikely you'll see Linux for it any time soon. But it's a beautiful, beautiful architecture to write code for. (And it's dual core! Not very many people know that...)

Comment: Re:Units! (Score 1) 216

Back in 2009, a UK artist set up an... installation, I suppose you'd call it... which was 1301 flourescent lighting tubes in a field under a 400kV megagrid power line. It's worth checking the pictures out, as they're actually quite striking:

The total amount of power used here would be negligible, of course. But I'm surprised they didn't come down on him for improper disposal of mercury...

God is real, unless declared integer.