标签: Raspberry

The emergence of low cost and easy to use do-it-yourself boards such as Arduino and Raspberry Pi have paved the way for an unprecedented boom in creativity among technology and application enthusiasts. Most of these enthusiasts are would-be developers and undergraduate students with an idea for creating a design, who often are limited in the necessary underlying technical know-how and experience but are willing to learn as they are doing.   No less profound and far reaching is the impact DIY hardware platforms have had on the domain experts. In addition to working engineers with expertise in a particular market segment, this category includes the graduate students and professors at universities and technical institutes. Rather than wile away months and even years on the electronic implementation details of getting a particular domain experiment going, such projects sometimes take only a few months using DIY boards.   My fascination with these specialists comes out of my experience at California Institute of Technology, where my job was defined as staff writer for the PR group and the alumni magazine. But I was also often called on to help grad students, post docs, and professors write articles about their research for popular science magazines, as well as to work with them on grant proposals and other documentation on their research projects.   In that context I saw first-hand how the lack of the right equipment and expertise, much of it computer-based, prolonged the time just to get to the point of actually doing the experimental work. Due mainly to the necessary "implementation details," before DIY boards it could be years before the actual experimental work could get started.   When I worked at Caltech in the 1970s, the age of microprocessors and microcontrollers had just started. The domain experts I worked with had to beg, borrow, or steal the appropriate computer hardware by sharing a mainframe, borrowing an unused minicomputer such as a DEC PDP or a Data General machine, or building their own using the bipolar, NMOS, PMOS, and CMOS MSI and SSI "bit slices" for Arithmetic Logic Units, registers and various digital signal processing functions as barrel shifters. Single chip microprocessors such as Intel’s 4040 and Motorola’s 6800 were still too primitive and did not have the processing power needed in most such projects.   As microprocessors and their software support in the form of the C-language and programming tools have become more common and powerful, the implementation details have taken less time. But with DIY boards such as Raspberry Pi and Arduino, the cost and the time to get a project to the point of collecting useful data has been reduced drastically. Now it is a matter of only weeks or months, not years. Instead of major grants to get started research projects can often be funded out of pocket by the researcher and a few friends and family, maybe some grad students interested in the project, or by crowd-funding on the Web.   Not only have the number of projects increased, the time required to complete projects has been drastically shortened. Using the regular online search engines, I find a couple of dozen academic research projects using DIY boards described each month. It’s clear that the combination of low cost and ease of implementation is opening up a range of projects for researchers that were not possible before, as well as funding possibilities beyond the traditional university and governmental grants. Here are just a few of the hundreds of recent such DIY-board based research projects that caught my attention:   Cloud services on the cheap. Researchers at Glasgow University have built a scale model for cloud computing infrastructure research using plastic Leggo Bricks and Raspberry Pi boards. The PiCloud test bed is used to study such things as the economics of provisioning, application scheduling, and resource discovery. Composed of 56 Raspberry Pi's, it cost about $2000, about 50 times lower than that for an X86-based implementation.   Using a combination of plastic Lego Bricks and Arduino boards, University of Glasgow researchers have built a low-cost cloud architecture test bed. (Source: University of Glasgow Photo Gallery (https://raspberrypicloud.wordpress.com/))   A $45 all-purpose mobile electrochemical detector.A team of researchers at the University of California, Berkeley, have built uMed, an Arduino-based petrochemical tester for use in tandem with a mobile phone. They use it for remote and low-cost collection and transmission to a cloud based servers of a range of analyses for personal and public health, clinical, food safety, and environmental monitoring.   Measuring mechanical vibrations in physics experiments. Researchers in the department of physics and astronomy at Uppsula University have used an Arduino-based board in combination with dual MEMS accelerometers to measure mechanical vibrations so that they can be eliminated and factored into the design of the measurement equipment for their experiments.   Plant phenotyping with a Raspberry Pi. To replace the largely manual methods of identifying the genotype (genetic structure) of new plant species by their appearance (phenotype), researchers at the IMT Institute for Advanced Studies in Luca, Italy, have developed a low-cost, automated method of visual analysis of plants using a Raspberry Pi-based board to study multiple plants growing in a laboratory test plot.     An Arduino-based uMED device tests a glucose test strip and sends the results to a low-end mobile phone through a standard audio cable. (Source: U.S National Academy of Sciences (http://www.pnas.org))   These are just a sampling of recent university research projects that now use DIY board platforms. Such projects cover the entire spectrum of knowledge domain specialties: social sciences, biology, genetics, climate, oceanography, nuclear physics, medicine, communications, and engineering disciplines of all sorts.   With government funding of research already going down, will this make it possible for universities and technical institutes to do more with less? Or will the use the of low cost of DIY boards be used as an excuse to reduce funding further? Or will Web-enabled crowd-funding of basic research, now still relatively rare, become the norm? What are the legal ramifications of such research? Who owns it? Who controls it? If it has both government funding and crowdfunding, who is top dog? It will take time for answers to these questions to become clear.   One thing I do know for sure: now, I would not be able to do work on as many projects at a time as I did when I worked at Caltech years ago. I was usually involved in five or six projects at a time because of the months or years it took to pull together and build the equipment for collecting data. Those hurry-up-and-wait stalled periods gave me plenty of wiggle-room in terms of multitasking my time. That would be impossible today, given the dramatically narrowed time it now takes to get a project to the point at which a researcher can get useful data.

The emergence of low cost and easy to use do-it-yourself boards such as Arduino and Raspberry Pi have set off an unprecedented boom in creativity among technology and application enthusiasts. Most of these enthusiasts are would-be developers and undergraduate students with an idea for creating a design, who often are limited in the necessary underlying technical know-how and experience but are willing to learn as they are doing.   No less profound and far reaching is the impact DIY hardware platforms have had on the domain experts. In addition to working engineers with expertise in a particular market segment, this category includes the graduate students and professors at universities and technical institutes. Rather than wile away months and even years on the electronic implementation details of getting a particular domain experiment going, such projects sometimes take only a few months using DIY boards.   My fascination with these specialists comes out of my experience at California Institute of Technology, where my job was defined as staff writer for the PR group and the alumni magazine. But I was also often called on to help grad students, post docs, and professors write articles about their research for popular science magazines, as well as to work with them on grant proposals and other documentation on their research projects.   In that context I saw first-hand how the lack of the right equipment and expertise, much of it computer-based, prolonged the time just to get to the point of actually doing the experimental work. Due mainly to the necessary "implementation details," before DIY boards it could be years before the actual experimental work could get started.   When I worked at Caltech in the 1970s, the age of microprocessors and microcontrollers had just started. The domain experts I worked with had to beg, borrow, or steal the appropriate computer hardware by sharing a mainframe, borrowing an unused minicomputer such as a DEC PDP or a Data General machine, or building their own using the bipolar, NMOS, PMOS, and CMOS MSI and SSI "bit slices" for Arithmetic Logic Units, registers and various digital signal processing functions as barrel shifters. Single chip microprocessors such as Intel’s 4040 and Motorola’s 6800 were still too primitive and did not have the processing power needed in most such projects.   As microprocessors and their software support in the form of the C-language and programming tools have become more common and powerful, the implementation details have taken less time. But with DIY boards such as Raspberry Pi and Arduino, the cost and the time to get a project to the point of collecting useful data has been reduced drastically. Now it is a matter of only weeks or months, not years. Instead of major grants to get started research projects can often be funded out of pocket by the researcher and a few friends and family, maybe some grad students interested in the project, or by crowd-funding on the Web.   Not only have the number of projects increased, the time required to complete projects has been drastically shortened. Using the regular online search engines, I find a couple of dozen academic research projects using DIY boards described each month. It’s clear that the combination of low cost and ease of implementation is opening up a range of projects for researchers that were not possible before, as well as funding possibilities beyond the traditional university and governmental grants. Here are just a few of the hundreds of recent such DIY-board based research projects that caught my attention:   Cloud services on the cheap. Researchers at Glasgow University have built a scale model for cloud computing infrastructure research using plastic Leggo Bricks and Raspberry Pi boards. The PiCloud test bed is used to study such things as the economics of provisioning, application scheduling, and resource discovery. Composed of 56 Raspberry Pi's, it cost about $2000, about 50 times lower than that for an X86-based implementation.   Using a combination of plastic Lego Bricks and Arduino boards, University of Glasgow researchers have built a low-cost cloud architecture test bed. (Source: University of Glasgow Photo Gallery (https://raspberrypicloud.wordpress.com/))   A $45 all-purpose mobile electrochemical detector.A team of researchers at the University of California, Berkeley, have built uMed, an Arduino-based petrochemical tester for use in tandem with a mobile phone. They use it for remote and low-cost collection and transmission to a cloud based servers of a range of analyses for personal and public health, clinical, food safety, and environmental monitoring.   Measuring mechanical vibrations in physics experiments. Researchers in the department of physics and astronomy at Uppsula University have used an Arduino-based board in combination with dual MEMS accelerometers to measure mechanical vibrations so that they can be eliminated and factored into the design of the measurement equipment for their experiments.   Plant phenotyping with a Raspberry Pi. To replace the largely manual methods of identifying the genotype (genetic structure) of new plant species by their appearance (phenotype), researchers at the IMT Institute for Advanced Studies in Luca, Italy, have developed a low-cost, automated method of visual analysis of plants using a Raspberry Pi-based board to study multiple plants growing in a laboratory test plot.     An Arduino-based uMED device tests a glucose test strip and sends the results to a low-end mobile phone through a standard audio cable. (Source: U.S National Academy of Sciences (http://www.pnas.org))   These are just a sampling of recent university research projects that now use DIY board platforms. Such projects cover the entire spectrum of knowledge domain specialties: social sciences, biology, genetics, climate, oceanography, nuclear physics, medicine, communications, and engineering disciplines of all sorts.   With government funding of research already going down, will this make it possible for universities and technical institutes to do more with less? Or will the use the of low cost of DIY boards be used as an excuse to reduce funding further? Or will Web-enabled crowd-funding of basic research, now still relatively rare, become the norm? What are the legal ramifications of such research? Who owns it? Who controls it? If it has both government funding and crowdfunding, who is top dog? It will take time for answers to these questions to become clear.   One thing I do know for sure: now, I would not be able to do work on as many projects at a time as I did when I worked at Caltech years ago. I was usually involved in five or six projects at a time because of the months or years it took to pull together and build the equipment for collecting data. Those hurry-up-and-wait stalled periods gave me plenty of wiggle-room in terms of multitasking my time. That would be impossible today, given the dramatically narrowed time it now takes to get a project to the point at which a researcher can get useful data.      

Lately, I have been having fun with a Raspberry Pi, showing it to fellow engineers and asking: “Find the CPU.” Most can’t.     Raspberry Pi – where’s the CPU?   The big chip is RAM. The next smaller one is a USB and Ethernet controller. There are no interesting parts on the bottom of the board. No chips are under the connectors. So where’s the CPU?   The arrow points to the CPU. Though even in person it’s really hard to see, the RAM chip is on top of the processor using a packaging technique common in the mobile phone business called “Package on Package” (PoP). In this case the CPU is soldered to the board, and the RAM to 168 balls on top of the processor package. Propagation delays go down and packaging density increases. Smaller is better, and we’re sure seeing this in the microcontroller world. Freescale’s ARM Cortex M0+ MKL02Z32CAF4R is probably the smallest ARM part at either 1.994 x 1.94 mm (according to the packaging documentation) or 2 x 1.61 mm (according to the datasheet, which later references the packaging docs). It’s in a wafer-level chip-scale package (WLCSP), where an entire wafer of ICs is fully formed, plastic, balls and all, and then individual devices are sawed apart. The silicon is exposed around the edges. MKL02Z32CAF4R in a WLCSP package I don’t have one of these handy for a comparison picture, but the next photo shows an ADP172Vage regulator in a WLCSP package. This device has four balls and is 1 x 1 mm, or half as long in each dimension as Freescale’s device. There’s not much to it, and I have no idea how one is supposed to prototype with these.   ADP172 WLCSP (1 x 1 mm) Perhaps the smallest CPU is Atmel’s 8bit ATtiny20-UUR, which is just 1.555 x 1.403 mm, not much bigger than the ADP172 shown above. It has twelve balls. Transistors have disappeared. Glance at a TFT screen and you’re looking through millions of transistors. CPUs aren’t far behind. Atmel and Microchip have long offered low-pin-count microcontrollers, which I think opens a huge range of applications where just a little intelligence is needed. Now Freescale is bringing 32 bits to the game, a great move. TI has some tiny 16bitters and NXP offers Cortex M0 parts in a package just a bit bigger than Freescale’s. To put this in perspective, when I was in college in the early 70s the school had one computer to service 40,000 students. The Univac 1108 was a 36bit machine that ran at 1.3MHz. There was no RAM of course, instead having one megaword of core, which is about 4 MB. The Freescale part, which is practically invisible, is 32 bits, runs at 48MHz, and has 1/100 the memory. So couple that 2 x 2 mm device with an SO16 4 MB RAM and, except for the I/O, a barely-visible system would have more power than the Univac. Add a 1 GB flash part and the system’s mass storage would exceed the 1108’s room-full of tape drives (50 MB per tape) and FASTRAND drum memories (99 MB each). Of course, the mainframe cost $10m (about $60m in today’s deflated greenbacks) and the Cortex-M0+ and memory would give you change from a ten dollar bill.   A 1970ish Univac 1108. A faster system using a Cortex M0+ and external memory would occupy about the space of the operator’s small fingernail. So where will it stop? How much smaller can components get yet still be amenable to reasonable assembly processes?  

    同事在年前的时候收到一个树莓派，知道我对硬件比较感兴趣，就让我试玩一下，对这种好事我向来都是不会拒绝的。只是年后的事情一直都比较多，没周末也杂事颇多，就给耽误了，今天终于空出时间来把玩一下这块板子了。对于树莓派(Raspberry Pi)的由来、参数什么的我就不介绍了，如果有不了解的，百度或者谷歌一下就好了。   据说这块只有信用卡大小板子的功能非常强大，你可以用它来开发各种酷炫的产品，包括机器人和可穿戴式电脑。在前不久深圳举办的Maker Faire上我还见到过一些创客用树莓派DIY的产品。不过我是还没打算用这块板子来DIY什么新奇的产品出来，那个以后再说，今天就先让它运转起来再说。   图1：树莓派开箱图。   图2：树莓派正面。   图3：树莓派反面。     由于我同事给我的只是一块纯粹的电路板，要想树莓派运行起来的，还需要自己准备一些东西，还好这些东西我家里基本都有。需要准备的东西有：4G以上的SD卡一张、5V 1A左右的电源一个、RJ45网线一根、USB接口的鼠标和键盘各一个、HDMI线一根和带HDMI接口的电视机或者显示器。   除此之外，还需要到树莓派的官网上去下载一个系统镜像，你可以选择只下载一个单独操作系统镜像，也可以下载NOOBS那个镜像。我选择的是NOOBS，这个镜像里面包含好几个操作系统，离线文件1.3G左右。   然后按照NOOBS里面的安装指南，又去SD卡的官方网站(https://www.sdcard.org/downloads/formatter_4/eula_windows/)下载一个格式化SD的工具，按照提示安装后，格式化SD卡，格式化的时候注意“格式化选项设置”里的“逻辑大小调整”需要选择开启。格式化后，将NOOBS解压缩后拷贝进SD卡。最后把SD卡插进树莓派上，连接好各种线后，就可以开机了。   图4：连接后线后的树莓派。   开机后进入安装系统的界面，如图5，在这里可以根据你SD卡的空间大小，选择安装一个或者几个系统。我选择了安装推荐的Raspbian系统和另一个可以播放视频的RaspBMC系统。选择好后，点确定就行了，然后就是等待了，跟我们安装Windowns系统的过程基本差不多。   图5：安装操作系统选择界面。   图6：操作系统安装过程。   操作系统安装完成后，就可以选择进入的系统了。我先进入Raspbian系统，启动过程会出现一系列的初始化命令行。然后就会出现一个类似电脑BIOS界面设置界面。在这个界面里可以设置树莓派是否以窗口模式启动、系统语言、更改密码、区域和时区等等。设置好后，点击完成。重新启动就可以进入窗口模式了。   图7：Raspbian系统界面。   现在看到的界面跟我们常用的Windowns界面差不多了，然后就可以尽情体验里面的乐趣了。还发现里面竟然还有一个Pi Store，商店里的几款游戏还是收费的。   图8：树莓派上网界面1。   图9：树莓派上网界面2   图10：Pi Store。   另外，发现鼠标不一定需要有线的USB鼠标，无线免驱动的鼠标也完全OK。这次的试玩就先写到这里了。      

If you are an 80s kid in the United States, you undoubtedly remember a toy called "Teddy Ruxpin." Your feelings of this bear likely range from fondness, such as happy memories of it "reading" you a story; dread, possibly fear; or curiosity about how it worked. Maybe you even felt some envy at the time if you didn't have one, likely replaced years later by curiosity about what made you want one.   Nearly 30 years later, you might again think upon that doll and realise that with modern microcontrollers, like the Arduino, this doll could be made into something different and debatably better than what it was originally intended for. Fortunately, if you'd like to start tearing into one, you can build on the excellent work of others. Mechanically, the bear is extremely simple, using one servo to control both the eyes and the mouth. Although I haven't personally disassembled one, I would guess that here is a mechanical linkage (possibly a cam) that keeps the eyes open while the servo travels through a certain range. This would allow it to actuate the mouth to "read" the story while the eyes stare creepily ahead until the servo was fully lowered. To get to the electronic goodies, you'll have to remove a flap on the back of the bear's shirt. The tape player then needs to be removed to get to the three servo wires inside the bear's body cavity. There are also two apparent power wired in this space, but if you're going to replace its centrally-located "brain" with your own controller, these likely won't be needed. There are some more pictures on wgz.org that help illustrate what is needed here. The other three wires can then be hooked up to your own controller solution for whatever mischief you'd like to cause with it. An Arduino, Raspberry Pi, or even a pyMCU come to mind. This article on Ars Technica uses an Arduino as a method for a computer to "possess" the bear, and sync up mouth movements with the Windows voice synthesiser. If one wanted to go even further, a Raspberry Pi would seem like an idea candidate for a stand-alone system. Going even further, I'd love to see one with servos embedded in the shoulders to allow for some crude arm movement, or maybe something to actuate the eyes. LEDs might be an even better solution to allow them to glow at opportune times. Of course, that doesn't even get into the possibility of using some sort of sensors for feedback. Maybe a passive infrared sensor could be used to surprise unsuspecting passers-by. It's not too early to think about your Halloween display this year! Taking a different tack, maybe you'd rather see 80 of them talking in sequence . Maybe a Bluetooth or WiFi connection could be used for something similar if a stand-alone system was devised. It seems like a strange thing for kids to want today, but it was the best selling toy of 1985-1986. On the other hand, maybe I just don't possess or understand the psychology of a 5-year-old anymore. This is probably a good thing. Finally, if you're wondering what a "Teddy Ruxpin" is, or just want a reminder, check out this YouTube channel for a sampling of what this little animatronic bear is all about . Jeremy Cook is a manufacturing engineer with 10 years experience and has a BSME from Clemson University.