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<BR>> But it also says that documentation on the ARM architecture is not freely available, and that indeed could be a problem.<BR> <BR>Did the author of that article even try to do a basic search of the documentation or is he trying to make his point by obfuscating the facts?<BR>Here's is the full Technical Reference Manual, including the programmer's model (for those inclined to roll their own assembly code), for the ARM11 core used in the R-Pi. You can download the full PDF (all 728 pages) if you wish peruse it offline.<BR> <BR><a href="http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0360f/index.html" target="_blank">http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0360f/index.html</a><BR> <BR>In general, I'm not sure I care much what CPU/SoC a system uses as long as we have a gcc port that can compile to that platform. What I'm really interested in is what kind applications/tools can we build to make these systems actually reach the target (education) market. Or even better, intuitive tools for kids to use to build their own applications.<BR> <BR>-Nilanjan<BR> <BR><div><div id="ecxSkyDrivePlaceholder"></div>> -----Original Message-----<br>> From: hardwarehacking-bounces+nilanjan.palit=intel.com@blu.org [mailto:hardwarehacking-bounces+nilanjan.palit=intel.com@blu.org] On Behalf Of Tom Metro<br>> Sent: Saturday, October 06, 2012 1:35 PM<br>> To: hardwarehacking@blu.org<br>> Subject: [HH] Raspberry Pi stuff: enclosure, Pi NAS, closed source not good for education<br>> <br>> Thanks to Stephen Adler for filming and posting his Raspberry Pi<br>> Video/Tutorial:<br>> http://www.mail-archive.com/hardwarehacking@blu.org/msg00487.html<br>> <br>> (I haven't viewed it, but will take a look when/if I get a Raspberry Pi.)<br>> <br>> <br>> Here's a fairly introductory Raspberry Pi tutorial that end with how to use a Raspberry Pi as a NAS:<br>> http://www.techradar.com/news/computing/pc/raspberry-pi-tutorial-how-to-do-more-1095946<br>> <br>> <br>> adafruit is promoting a colorful new Pi enclosure that is made of a rainbow assortment of laser cut acrylic that stacks up and is sandwiched between a top and bottom layer of clear acrylic:<br>> http://www.adafruit.com/blog/2012/09/20/in-stock-pibow-enclosure-for-raspberry-pi-computers/<br>> <br>> <br>> Why One Person Thinks Raspberry Pi Is Unsuitable For Education http://hardware.slashdot.org/story/12/09/25/2056240/why-one-person-thinks-raspberry-pi-is-unsuitable-for-education?utm_source=rss1.0mainlinkanon&utm_medium=feed<br>> <br>> (Quoting Slashdot, which quotes the original article,<br>> http://whitequark.org/blog/2012/09/25/why-raspberry-pi-is-unsuitable-for-education/)<br>> <br>> "Raspberry Pi was designed for education. As any popular product is<br>> bound to, Raspberry Pi has been criticized a lot for things like lack<br>> of a box, absence of supplied charger or even WiFi. Raspberry Pi has a<br>> much more fundamental flaw, which directly conflicts with its original<br>> goal: it is a black box tightly sealed with patents and protected by<br>> corporations. It isn't even remotely an open platform."<br>> <br>> The "proprietary GPU blob needed to boot" is mentioned, which has been discussed here before. The article also touches on the ARM being patented, which I don't have a problem with. But it also says that documentation on the ARM architecture is not freely available, and that indeed could be a problem.<br>> <br>> It goes on to list some completely open source CPU cores, as well as pointing out other proprietary vendors, like Atmel, have freely shared their documentation without onerous licensing restrictions.<br>> <br>> The author recommends the more open Beagle Board or Samsung ODROID-X as a Raspberry Pi alternative. He also recommends the fully open hardware Milkymist One, but it costs $800 and thus isn't a practical alternative.<br>> I guess he wasn't aware of some of the other open hardware boards that are in the same league as the Pi and still fairly cheap.<br>> <br>> Rhombus Tech (http://rhombus-tech.net/), a company creating an open hardware platform, was mentioned in the Slashdot comments. (Not terribly unique. I posted about another Raspberry Pi-class device recently<br>> (OLinuXino-Micro) that was open.) The Rhombus Tech products will use a PCMCIA-like metal-enclosed card design, and their first model will use an Allwinner A10 CPU.<br>> <br>> The full article is worth a read.<br>> <br>> The Slashdot blurb also references:<br>> <br>> Raspberry Pi's Secret: 'Sell Out a Little to Sell a Lot'<br>> http://www.wired.com/opinion/2012/09/raspberry-pi-insider-exclusive-sellout-to-sell-out<br>> <br>> ...if other manufacturers copied the design, our partners would lose<br>> their investment, which was approaching several million dollars.<br>> <br>> How could we enable hacking while preventing cloning? Holding back the<br>> schematics altogether troubled us. Not being open would impede<br>> people's ability to interface and hack the hardware - defeating the<br>> very goals we had set out to accomplish with Raspberry Pi in the first<br>> place.<br>> <br>> So we decided to publish the schematics, but hold back the detailed<br>> Bill of Materials (BOM) and physical PCB design or "Gerbers" for a<br>> limited amount of time. After all, hardware is just one part of our<br>> overall plans. The schematics alone don't provide enough information<br>> to clone the Pi without expending considerable effort re-laying the<br>> PCB and figuring out the exact part used in each location.<br>> <br>> Ummm...if Broadcom is one of the partners, and the product depends on the Broadcom SoC that in turn requires a proprietary software blob, it would seem they already had two hard to bypass barriers to cloning:<br>> Broadcom could refuse to sell the SoC, or it could shut down the clones for copyright violation. Was Broadcom not cooperative?<br>> <br>> Here's an interesting bit on the board fabrication:<br>> <br>> ...we had 253 connections to bring out (the BGA escape) in an area<br>> much smaller than the size of a dime. And while there are special<br>> high-density interconnect (HDI) techniques for densely layered PCBs,<br>> those would just reduce yield and increase processing steps not to<br>> mention the costs. ... What if we could steal the idea of "blind micro<br>> vias" from high-density interconnects, but apply it cheaply enough for<br>> the Pi design?<br>> <br>> Instead of going through all the PCB layers, we made human-hair sized<br>> holes (micro vias) that go through only the first couple of layers<br>> (blind) - saving just enough space on the other layers for wiring up<br>> the other PCB components. At high volumes, these holes could be made<br>> quickly and efficiently with a laser. And it only cost a few cents<br>> extra. Making these tradeoffs resulted in a relatively simple<br>> six-layer board that didn't compromise power distribution. And it<br>> enabled manufacturing at scale.<br>> <br>> Seems like another good way to ward off clones, unless this technique is widely known.<br>> <br>> -Tom<br></div><div> </div> </div></body>
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