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Comment Re:its not selling well (Score 1) 83

Can it do anything my Blackberry can't?

It runs the software that you write, and you don't even need any SDK for that. Out of the box it runs Lua, Python, Tcl, Octave, Scheme, gForth, Emacs-Lisp, Shell Script and who knows what else. There's even a GCC toolchain package available, if you need it. If you're satisfied with the software that vendors throw at you or allow you to obtain via their managed app-store, than maybe NanoNote is not made for you.

Wireless Networking

Submission + - NanoNote goes Wireless (

dvdkhlng writes: "Even though completely copyleft, the NanoNote hand-held platform failed to get the attention of many due to its low specs and the lack of wireless connectivity. The objective to keep things open had its price, and especially wireless technology is a mine-field of patents and NDAs.
Now a few gifted hackers designed an add-on card to bring wireless to the NanoNote. It's not what you would expect: WLAN compatibility was sacrificed, going for the less encumbered IPv6 over 802.15.4 standard instead. The resulting dongles won't win a price for the highest bandwidth but excel at simplicity, energy efficiency and manufacturability.
Want to see the ugly details? Designs, source code and production documentation are published under open source licenses."

The Almighty Buck

Ask Amir Taaki About Bitcoin 768

"Bitcoin," says the project's website, "is a peer-to-peer currency. Peer-to-peer means that no central authority issues new money or tracks transactions." Wikipedia offers a readable explanation of the underlying technology. In (very) short, Bitcoin uses a distributed database and public key encryption to allow users to reassign ownership of units of Bitcoin currency (BTC), and does so in a way that can keep the user's identity private. Bitcoin isn't yet accepted the way credit cards are, but it's more than theoretical. You can buy (some) things with Bitcoin, and trade the currency itself. Now, you can ask question about Bitcoin of Amir Taaki, a developer of client interfaces and stock trading software for Bitcoin, and owner and operator of trading exchange Amir requests that questions focus not "so much on the mining (too many people get focused on that when it's a minor aspect of Bitcoin) nor simple technical questions (people can go find that info themselves on Wikipedia/the forums/sourcecode)," but rather on the harder-to-answer questions. Reading some of the related stories listed below may give you ideas on what those are. Standard Slashdot Interview rules apply: ask as many questions as you want, but please keep them to one per comment. Amir will get back with his answers.

Italy Votes To Abandon Nuclear Power 848

ElementOfDestruction writes "Italy has joined Germany in halting the production of energy from atomic power generation. This differs from Germany in that the Italian decision was made by a public vote, rather than a government mandated shutdown. 57% of Italian Households voted in this public measure. While democracy should trump all, is it wise to hold majority opinion so high that it slows down progress?"

Submission + - A Free and Open Replacement for Wireless LAN ( 3

dvdkhlng writes: Qi-Hardware, the community that brought us the Ben NanoNote handheld computer, have just released their next piece of all-out free and open hardware: the AtBEN+AtUSB wireless dongles. Aiming for a solution that works without proprietary firmware blobs, WLAN compatability was abandoned. Instead the project went for simpler, yet more open 6LowPAN technology.

The first batch of AtBen+AtUSB dongles is now ready for shipment trough Tuxbrain. Designs and source code are available under GPL and CC licenses.

Comment Re:ok (Score 2) 99

Freescale iMX51 and TI OMAPs are completely proprietary, AFAIR. If at all you'll only get closed-source drivers for their built-in GPUs. That doesn't make them very sexy for such open-source hardware projects. Also I guess you'll soon run into real-time execution problems, if the GPU drivers aren't 100% perfect. Even with my ATI card I have these problems from time to time (something flushing GPU pipelines? no clue.). This FPGA CPU with RTOS kernel and custom-made 2-D acceleration will allow you to get perfect frames, all the time.

Comment Re:One right here! (Score 1) 441

[..] To this day, the only thing I find lacking is multimedia players (and I especially miss Winamp).

Did you try the Audacious audio player? It was once forked from XMMS, which was a pretty good Winamp clone (for me anyways, haven't seen any Winamp since the year 2000 :). I still have Audacious configured to start with the XMMS skin, which is pretty close to how Winamp looked in 2000. With regard to media players, there's quite a lot of stuff around. Mplayer is certainly the best-performing media player on Linux. If you prefer a nicer GUI, there's also VLC. When you need more codecs, install Ubuntu package ubuntu-restricted-extras, and/or add the medibuntu repository to your package sources.


Submission + - Consumer device with open CPU out of beta soon (

lekernel writes: "After years of passionate and engaging development, the video synthesizer from the Milkymist project is expected to go out of beta in August.
Dubbed "Milkymist One", it features as central component a system-on-chip made exclusively of IP cores licensed under the open source principles, and is aimed at use by a general audience of video performance artists, clubs and musicians. It is one of the first consumer electronics products putting forward open source semiconductor IP, open PCB design and open source software at the same time.
The full source code is available for download from Github, and a few hardware kits are available from specialized electronics distributors."


Submission + - Micro-SD Card Slot Abused as VGA-Port (

dvdkhlng writes: The guy who did this calls it an "unexpected capability". The Ben NanoNote open-source hand-held computer has often been criticized for not being very extensible hardware-wise. A community-effort now starts to challenge this by shipping the so-called UBB board, that plugs into the micro-SD port, making 6 I/O lines available to hardware hackers. The most impressive use so far is this VGA port implemented by just a few resistors, with signal-generation mostly controlled by software. Schematics and source code are available under the GPL.

Comment Re:Oh stop with the supercomputer bullshit (Score 1) 240

Ok sure, go ahead and run a 8k x 8k Linpack, tell me how that goes and how non-limited you are.

I guess if 8kx8k Linpack refers to matrix multiplication, I'm pretty sure that the Cell will perform at close to its 200GFLOP/s performance. Matrix multiplication can be really well broken down into block-matrix multiplications that nicely fit in the 256KB of available SRAM. Data transfer cost per block grows O(N^2), while FLOPs grow O(N^3). With 64x64 block matrixes you have to transfer 2*64*64 floats while having to compute 32 times as many multiply&adds. With 8 SPUs sharing the single XDR RAM you'll only have bandwidth to transfer 1/4 float per cycle and core. However, corresponding to that transfer rate, the core has to compute 32*1/4=8 madds per cycle, which happens to be twice the theoretical peak performance of the core. So no bandwidth problem at all. You'll be able to increase block size to 96x96 if you want to reduce bandwidth per FLOP even further. this paper claims close to peak performance for 2304x2304 sized matrices.

Sorry man, the Cell is fine for some things but the idea that it doesn't face the same realistic limits other hardware does is silly. You can talk all you like about high speed stuff on the cache, but that applies only for things that'll fit in there. When you have larger problem sets that have to go back and forth to main memory a lot, I'm afraid it isn't so fast.

You'll have these kind of losses on any architecture, including GPUs. What i'm saying is that the Cell is designed so that you'll almost always be able to reach close to 100% utilization of the available peak FLOP/s. That is something that you won't ever normally achieve on a GPU. On the other hand, GPUs have a much higher peak FLOP/s so loosing half of that due to bandwidth problem seems to be more acceptible.

Regardless my point was simply how unrealistic it is to call the thing a supercomputer. If a couple hundred GFLOPS makes a supercomputer then my GPU is a supercomputer.

Don't downplay what GPUs can do computationally either. They are the kings of Folding, yes ahead of the PS3. So long as your problem meets some requirements (highly parallel, single precision FP, fits in to GPU memory, not a lot of branching and when it branches everything branches the same direction) they scream. Is that all things? No, certainly not, you can find things they drag ass on. However the same happens with the Cell when compared to something like a Core i7. For some things, due to the SPEs the Cell is faster, however for others, due to constraints of the PPE it is slower.

Well it's not the constraints on the PPE that make the Cell slow. The Cell is just as fast as 200GPLOP/s can be. Modern GPUs are much faster than that, even if they cannot utilize all their horsepower. The downside is that GPUs rely on very different programming&compiler paradigms, where Cell was designed to mostly use multi-core, shared memory pradigms and standard C compilers with SIMD extensions, everything nicely managed by a standard MMU-utilizing operating system.

It is an interesting architecture and useful for some things, but it is not particularly impressive compared to other modern processors. Doesn't mean it is worthless, just that it is not "OMG this is so fast!".

It was that fast when it came out. Unfortunately development of the successors was cancelled by IBM, probably due to GPGPU programming eating its lunch.

Comment Re:Oh stop with the supercomputer bullshit (Score 5, Informative) 240

The best they claim is 25.6 GFLOPS per cell in theoretical performance, so 205 GFLOPS is the best you theoretically get, if there are no bandwidth constraints (which there are on a PS3) for single precision math. Ok well testing my actual Radeon 5870, I get 800 GFLOPS for single precision, 227 for double precision. That is an actual benchmark of the card running on my desktop.

As somebody who programmed Cell CPUs for signal processing (including to, but not limited to PS3s), let me tell you that the PS3's memory bandwidth is so close to unlimited, that you usually don't have to think about it. At least as long as you move data only on the Element Interconnect Bus, between the 256KB local SRAMs of each CELL core, which is sufficient for most of what I did. It moves up to 200 giga bytes per second, maximum 16 bytes per 2 cycles in and out per core. The DMA engines that do those transfer have their own 1024bit (!) read/write port into the SRAM, so they burst 128 bytes per cycle into the SRAM, and don't have to steel many RAM cycles. The wikidedia article has more details.

In my experience, you can usually come pretty close to the 200 GFLOP/s of the Cell-CPU. When relying on C-Compiler with SIMD intrinsics, you usually manage 100 GPFOP/s for algorithms that have as many read/write opcodes as arithmetic opcodes. Smaller problems can mostly be handled on registers only (per CPU we have 128 16-byte registers!) and will run even faster.

Also note that many algorithms nowadays are not bandwidth but memory latency limited. Having the Cell's per-core DMA engines do background transfers to large local S-RAMs, mostly eliminates these latency problems and is much cleaner than relying on CPU caches guessing what parts of RAM to prefetch next. BTW these are user-space DMA engines that undergo page translation and are fully compatible to unix vm concepts. Still programming directly accesses DMA registers and doesn't need any kernel calls.

Try to do that with your GPU!

Comment Re:At some point, it's just bashing... (Score 1) 120

Darwin, the core of Mac OS X, is open source, for example, as well as Webkit, Apple's browser layout engine used in most browsers today, including Google Chrome and Android. And Grand Central Dispatch. And FaceTime. I could go on.

I won't say that this argument proves much about Apple's attitude towards openness. Webkit is based on KHTML which is LGPL and authorship not residing with Apple, so they absolutely had to open it up to satisfy the license.

The Darwin kernel is based on other free software work (mostly BSD?), BTW. No, the BSD license might not force Apple to open-source it, but it doesn't hurt so much, open-sourcing code that's freely available anyways.

Comment Re:It's all about maths, you insensitive clod! (Score 1) 448

1 picosecond (ps) is 10^(-12) secs. You can run a single instruction in a 1000 GHz CPU (please scale to your favourite multicore system) during 1 ps.

Actually you cannot even run a single instruction during 1ps. Modern CPUs are pipelined and make it look like an instruction takes one cycle. However, between loading of input, processing, and output, ca 20 cycles pass. It's just that with 20 instructions in the pipeline, you might get an effective throughput of 20 instructions per 20 cycles. And this does not even consider cache/memory and i/o access times.

Total I/O latency between signal arriving at PC, and PC answering may well be in the order of many 100 (if not 1000) cycles.

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