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Raspberry Pi Gertboard In Action

An anonymous reader writes with news from Geek.com on an expansion board for the Raspberry Pi. Quoting: "In the middle of December last year the Raspberry Pi Foundation made a surprising announcement that not only would we see the $25 PC released in 2012, it would also be getting an expansion board ... called the Gertboard, and is being developed by Broadcom employee Gert van Loo in his spare time. When completed, it will allow Raspberry Pi owners to play around with flashing LEDs, electric motors, and a range of different sensors. It effectively takes the $25 Raspberry Pi beyond just being a very cheap PC. There's a video of the Gertboard already working which demonstrates the 12 LEDs being lit up and the board powering an electric motor more than capable of lifting something like your garage door."

26 of 191 comments (clear)

  1. Neat! by JoeMerchant · · Score: 4, Funny

    Take that, Arduino.

    1. Re:Neat! by glop · · Score: 4, Insightful

      They have 13$ arduinos... That said, I prefer a Linux machine that can run python, java, apache and everything and then just talk to some IO library or something to take care of moving motors etc.
      But that's because I am a software guy....

    2. Re:Neat! by Joce640k · · Score: 4, Funny

      Yeah, programming under Linux is way easier then programming an Arduino...

      --
      No sig today...
    3. Re:Neat! by randomErr · · Score: 3, Informative

      From http://www.raspberrypi.org/archives/260

      Model B owners using networking and high-current USB peripherals will require a supply which can source 700mA (many phone chargers meet this requirement). Model A owners with powered USB devices will be able to get away with a much lower current capacity (300mA feels like a reasonable safety margin).

      --
      You say things that offend me and I can deal with it. Can you?
    4. Re:Neat! by fuzzyfuzzyfungus · · Score: 5, Interesting

      I suspect that(while they will probably be of assistance to geeks brewing their own) this will suffer the same fate as all the prior 'automated house' widgetry(a market at which they've been hammering for bloody ages now, with comparatively little success).

      Suitably motivated geeks, with some major time and pains, and more money than they initially expected to shell out, will indeed hammer out home automation systems. Fundamentally, home automation is a series of really-not-all-that-ghastly problems in AC wiring, switching, sensors, and logic. It will be utterly non-inter-operable with anything else(save perhaps the geek's cellphone of choice, for which he will build a website/app, and possibly an appliance or two into which he will hack directly. Nothing else.)

      Joe User, on the other hand, will discover that specific home automation products(eg. cheap programmable thermostats) can be purchased at any hardware store; but more sophisticated systems either pretty much suck, enough that they are really just starting parts for dedicated geeks(eg. X10), or can be purchased, from an installer, in one big, shiny, expensive, bespoke, proprietary package. It'll start at $10,000, be really slick, and interoperate with absolutely nothing that isn't itself.

      The various utility companies attempting to deploy "smart meters" for some combination of PR, easier meter reading, and customer behavior metrics will utterly ignore this, since it doesn't comply with their alphabet soup of semi-open-for-interoperability's-sake-but-not-at-all-talked-about-outside-the-industry-or-intended-for-you-to-know-anything-about wireline and wireless protocols(their status seems rather analogous to the state of various 'standards' in the wireless telco wars. Some of them are just totally proprietary, dreamed up by some company large enough that its service area qualifies as a large scale deployment. Others, GSM-like, are standardized cross-industry things; but are really not intended to be fiddled with by end users.

      All in all, no difference:

      There will still be nothing resembling manufacturer support for appliances that can report and control intelligently(as opposed to just having an external relay cut them on and off, with the exception of a few horrible manufacturer gimmicks that will probably be badly broken and tied to some manufacturer 'portal'. Geeks will continue to homebrew functional, if slightly rough, systems; and it will still be possible to buy very shiny, tightly integrated, totally proprietary widgets for large buildings and custom installs of various sorts.

      What dogs 'the automated house' seems not to be a lack of cheap computing power(wireless and fast CPUs certainly helps; but ASM coded PICs communicating over some primitive serial bus through your house's telephone wiring back in the late 80's could have handled it, with some sort of frontend/master-control widget similar to the x86/DOS based CNC machine control systems that persist to this day. Expensive? Yeah. Doable? Yeah.) It seems to be a combination of limited incremental benefit(power just doesn't cost that much, in many locations, doing it manually works OK, for most tasks, setup is currently complex, many locations charge residential customers the same for on and off peak power, so who cares?), complete lack of anything resembling standardization(minimal standardization of even simple things like remote control switches, never mind any sort of direct intelligence built into appliances that can be exposed. PCs have it, in a somewhat clusterfucked way, with ACPI; and some individual devices, like higher end furnaces, might have a manufacturer specific control panel on an HTTP server somewhere; but everything else is largely silent), and some degree of sinister intent by certain entities(the intentions of the power-rationing, 'consumer-metric'-gathering, and similar 'smart-meter' entities are largely not in your interest...)

      It's a pity: If it were a primarily technological problem, technology would have curb-stomped it by now. It isn't.

    5. Re:Neat! by Xenkar · · Score: 3, Informative

      I used to be an electrician, but then I took an arrow to the knee. Just kidding, a bone tumor broke off, caused an false aneurism, and doctors played copay ping pong with me for a month. I was left unable to work due to nerve damage.

      But before that, I used to work with 14 gauge wire, 12 gauge wire, and 10 gauge wire. It is significantly harder to route 10 gauge wire. Even more so if you already have insulation and drywall up. Perhaps things will be different with the 10 gauge equivalent graphene wire gets mass produced at a reasonable price, but until that day you'll need to accept that electricians will charge you extra for the inconvenience of having to deal with 10 gauge when 12 gauge probably more than met the hot tub's requirements.

    6. Re:Neat! by Anonymous Coward · · Score: 5, Informative

      Arduino programming language (Processing) is very similar to Python or interpreted C.

      No, arduino programming is NOT very similar to python at all. Its not even close.

      Arduino's native programming languages are C, C++ (with some limitations), and AVR assembler. That's it. The confusion comes from the fact Arduino purposely attempts to obscufate the fact you are using realatively low level languages behind a nice, high level API. None of these are close to python.

      When I first started using Arduinos, it took me a week before I figured out the imaginary "script language" everyone talks about, which I could never seem to find, doesn't actually exist. Its completely imaginary. Its 100% marketing and obscufation for C and C++.

    7. Re:Neat! by Anonymous Coward · · Score: 3, Insightful

      You know, to set the value of a GPIO pin on an Arduino you just make a single call to digitalWrite(). To trigger a stepper motor you have to toggle the pin's value, which requires (gasp!) two calls to digitalWrite. The equivalent under Linux involves opening the GPIO device file and making multiple read and write calls. For anyone who's ever run a stepper motor using an Arduino the overhead involved in all that boggles the mind. Really, ease of access to the GPIO pins is the least of your considerations when comparing Arduino to RaspberryPi.

      For embedded applications involving motors and servos the Achilles heel of Linux is real-time control. If you Google around for projects which use Linux boards for motor control you'll find people discussing wobbly servos and problems with interrupt latency. There are hacks which add a real-time layer under Linux but in general they have not been embraced by the Linux distros and are not well supported.

      I've done a few Arduino projects involving stepper motors and servos. My latest project requires much more than an Arduino can deliver so I'll be using a BeagleBoard running Linux. The motion logic will be offloaded to an Arduino and the two boards will talk to each other over a serial line. This sounds complicated but it will be much easier to maintain than a custom RTOS Linux hack and will give us complete and control over the timing aspects of the motors and servos.

      Frankly, comparing Arduino to something like a BeagleBone or RaspberryPi baffles me. They are very different devices with very different applications. For most of my Arduino projects Linux would have added nothing of value. And for my latest project a bare Arduino wasn't nearly powerful enough. Entirely different worlds.

  2. Excellent! by homb · · Score: 4, Interesting

    I'm very excited about this.
    Especially as a learning tool for my kids, I think that by seeing what is happening they'll get very excited about learning to program.
    I already have arduino boards, but it's not the same thing. Here we have a completely self-contained computer with great practical I/O interfaces.

  3. Through-hole by Anonymous Coward · · Score: 3, Insightful

    Who are these people who keep on insisting on using through-hole components? That board could easily be the same size as the Raspberry-pi board itself simply by using SOIC packages as opposed to DIP for all of the ICs. Soldering a 1.27mm pitch SMT component is really easy, it takes about the same amount of time as a DIP component, and is much, much, smaller.

    I understand from the Raspberry-pi website that it's gonna be supplied as a bare board + components, but like I said, soldering SMT stuff is really easy. Also if the whole point of this Raspberry-pi stuff is to teach people new skills, why not teach them how to solder stuff that the rest of the world is now using.

    1. Re:Through-hole by Anonymous Coward · · Score: 4, Informative

      Soldering a 1.27mm pitch SMT component is really easy, it takes about the same amount of time as a DIP component, and is much, much, smaller.

      No.

      Perhaps to a seasoned EE or hobbyist who gets his hands dirty on a daily basis, but otherwise, no.

      The best way to turn the Raspberry Pi to shit (apart from its name - "Acorn", the obvious predecessor to this whole project, sounded much better) would be to set the bar at a level which assumes you already know what you're doing before you've even started.

    2. Re:Through-hole by vlm · · Score: 4, Informative

      Who are these people who keep on insisting on using through-hole components? That board could easily be the same size as the Raspberry-pi board itself simply by using SOIC packages as opposed to DIP for all of the ICs. Soldering a 1.27mm pitch SMT component is really easy, it takes about the same amount of time as a DIP component, and is much, much, smaller.

      Its a meme that just won't die. As a guy who's been doing SMD at home on and off since the 80s for ham radio microwave gear, it gets tiring hearing for about three decades that what I find easy to do and enjoyable is "impossible" and will be the "death of homebrewing" and all that rot. Its right up there with "PL-259s are impossible to install" and "power poles are impossible to install", you only hear about it over and over from the 0.1% of the population who really can't do it.

      I'm willing to bet there are some very young hardware hackers on /. right now emulating their elders by rambling about how impossible it is to do SMD at home, despite my experience doing it for years before they were born.

      --
      "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
    3. Re:Through-hole by Anonymous Coward · · Score: 5, Informative

      *disclaimer* I work for Broadcom in the team that did 2835, however I am not involved with the Pi, so posted anon to not to be accused of karma-ing

      Reasons For through hole:
      1) Hobbyists aren't scared of them - some are scared of SMT (and some SMT is used on Gertboard)
      2) Requires less skilled soldering - yes a skilled solderer can do smt with ease, but half the point of this project is that it should be unintimidating to everyone.
      3) More mechanically sturdy. Useful for many hobby projects

      The Pi mainboard got in trouble for being none through-hole, and not available as a kit of parts, now Gertboard is in trouble for being exactly that.
      *sigh* this is why we can't have nice things.

    4. Re:Through-hole by Defenestrar · · Score: 3, Insightful

      I've soldered plenty of SM components myself, but you may be overlooking the novice oriented aspects of this system (and the comments you dismiss), especially when it comes to the tools available. Besides, practice only takes you so far; even an experienced plastic surgeon may have a hard time making something look pretty if he's only got leather-working tools available.

      If you consider that the computer is marketed as cheap, and this board is an educational add on (presumably also cheap) (well the board is functional, but the article points out the educational advantages, including the population), then it would probably be safe to assume that the soldering iron will also be cheap. A soldering iron allowing comfortable SM work is easily double or triple the cost of the computer - over an order of magnitude for the good ones. So, if one were to use a soldering iron of comparable or less cost than the system (what a novice may choose to start with), SM could be very hard if not impossible.

  4. Unsure about the gert... by Crookdotter · · Score: 3, Insightful

    I know, it's great and all, but if you're using the pi to do the heavy lifting, and the gert as simply a way to output, doesn't an arduino already do this, and with linux too? Is this redundant, or have I missed something?

    1. Re:Unsure about the gert... by Andy+Dodd · · Score: 5, Informative

      Arduino doesn't run Linux.

      This is more similar to a BeagleBone prototype cape - except with the Gertboard don't expect to be able to use any features in the chip that aren't put into the kernel by Eben and Gert. Unlike the CPU in the Arduino (ATMegaXX8) and the CPU in the BeagleBone (TI AM335x), the technical reference manual for the Broadcom chip in the Pi is completely unavailable. If support for anything is left out of the kernel, whether intentionally or simply due to lack of time, you will not be able to implement it yourself. If support for anything is broken in the kernel, you will have to live with it due to lack of documentation and the fact that Broadcom never comments their damn kernel code for anything. (Look at the BCM4330 driver for mobile devices as an example - if it misbehaves, you're screwed.)

      --
      retrorocket.o not found, launch anyway?
    2. Re:Unsure about the gert... by Crookdotter · · Score: 3, Informative

      Yes, that's my point. You've got the choice of:

      R pi + Gertboard

      or

      R pi + Arduino

      Both would be developed on the host linux PC, but Arduino is already rather mature and well supported, and connects via USB with no soldering to your shiny new Raspberry pi. What's the gertboard bringing to the table in addition to what the arduino does already?

    3. Re:Unsure about the gert... by Vairon · · Score: 5, Informative

      There are some aspects that are redundant but there is a lot more that is not. Here are some major differences:

      Arduinos do not run Linux. Their code is written in Assembly, C or C++ but WITHOUT the STL. There is no OS or kernel. It's pure monolithic code running on a Atmel Atmega328, ATmega2560 or similar processor. They support Analog I/O, Digital I/O, I2C, SPI, 1-wire, EEPROM, Serial communication via digital i/o lines or Serial over USB, typical 16Mhz clock speed and 8k of RAM, 32-256K of program storage. It probably uses slightly less power than the Raspberry Pi.

      Raspberry Pi do run Linux. Their code is written in any language supported by an ARM 1176JZF-S CPU with a Linux kernel such as Assembly, C, C++ with STL, Python, Perl, etc. There is a OS such as Debian, Arch with more to follow and a Linux kernel. Code written is traditional Linux code running in a multi-tasking system such as Linux provides. It's run on an ARM 1176JZF-S CPU. They support Digital I/O I2C, SPI, Serial communication via digital i/o (gpio) lines, SD card support, composite video out, HDMI video out, RCA audio out. 700Mhz clock speed, 128-256MB of RAM, 1-32GB of program storage (depending of SD card size).

      Unlike the Raspberry Pi, the Arduino cannot be developed on by itself. It requires another computer running Linux, OS X or Windows in order to develop on them.

      The Gertboard is more akin to what an Arduino shield is for an Arduino. It's just something you plug into a Raspberry Pi to provide access to more of the GPIO pins of the Raspberry Pi's SOC and it has some convenience functionality like LEDs built-in. Like an Arduino shield, it's optional. You can still use GPIO pins on the Raspberry Pi without it.

  5. Re:Raspberry Blob by Anonymous Coward · · Score: 5, Informative

    Plug it into your tv or ancient flatscreen. Wifi signal your video feed over the air for 25usd and some coding.

    I think your imagination is useless.

  6. Re:Quit yer yapping and start producing! by Speare · · Score: 5, Informative

    It IS in production, it just hasn't come out of the production pipeline yet. The working beta boards (with a hand-applied last-minute fix) are being auctioned off, proceeds for the charity recipients for which Raspberry Pi was created: making classroom computing happen.

    I will be happy to buy a bunch when they're available too, but let's watch the development. As for Tesla, did you buy the Roadster, seeing as how it's been available in showrooms for some time now?

    --
    [ .sig file not found ]
  7. Re:Raspberry Blob by Toonol · · Score: 4, Insightful

    The Raspberry Pi is a good litmus test for imagination. If you read or talk about it and have a tingle, you have an imagination. If you think it's pointless, you're dead inside.

  8. Re:Hardware folk shouldn't write code by FunkyELF · · Score: 3, Informative

    Python makes everything cleaner.

    # Make the 17 GPIO file systems & set them to output mode
    for g in gpiotbl:
            with open('/sys/class/gpio/export', 'w') as fout:
                    print >> fout, "%d" % g
            with open('/sys/class/gpio%d/direction' % g, 'w') as fout:
                    print >> fout, "out"

    # light effect on buffers
    for rep in xrange(5):
            for g in gpiotbl[:12]:
                    with open('/sys/class/gpio/gpio%d/value' % g, 'w') as fout:
                            print >> fout, "1"
                    sleep(TIME)
            for g in gpiotbl[:12]:
                    with open('/sys/class/gpio/gpio%d/value' % g, 'w') as fout:
                            print >> fout, "0"
                    sleep(TIME)

    test_motor()
    test_motor()

    sys.exit(0)

  9. model-A is damn close to 1 watt Re:Neat! by Fubari · · Score: 3, Informative
    They're using 5v over micro usb. Model-A's 300mA works out to 0.3A*5V = 1.5 watts. Model-B's 700mA is 0.7A*5V=3.5 watts. (I'd go with Model B just to double the ram (256MB) + ethernet.)
    While the gp will have to account for the efficiency of their power supply as well, I'm pretty impressed w/the rPi. It looks really cool. Here is a nice nice overview, the power-suppy section links to the parent's "archives/260" reference.

    From http://www.raspberrypi.org/archives/260 Model B owners using networking and high-current USB peripherals will require a supply which can source 700mA (many phone chargers meet this requirement). Model A owners with powered USB devices will be able to get away with a much lower current capacity (300mA feels like a reasonable safety margin).

  10. Please get it through your heads!!! by Anonymous Coward · · Score: 4, Insightful

    Arduino and Raspberry Pi are not competators in any way. They target two different markets whereby they have very slight overlap for hobbiests. The Pi simply can not compete with Arduino/AVR on the low end and Arduino/AVR can not compete with RPi on the highend. There's only a tiny intersection between the two and that's likely only because you have one or the other whereby a "close enough" solution is satisfactory.

    AVR/Arduino has solutions in the $1-$6 range, if you want to use an inexpensive ISP and break out the coresponding pins on your bare bones or really bare bones controller. Not to mention, the pins are easy to access with a multitude of more pins available. It also has some capabilities which are simply not available without a Gert board, which makes the pi all the more expensive. Furthermore, an RPi is basically as barebones as you're going to see - at least for a while - if ever. Whereas for the AVR/Arduino solution makes it easy to transplant your Arduino project into a barebones $3-$9 project.

    Furthermore, these two projects are really far and away much more complimentary technologies than they are competators. Basically, let the RPi do the heavy CPU lifting and the AVR's do the GPIO and bit flipping. Its a combination made in heaven.

    1. Re:Please get it through your heads!!! by Joce640k · · Score: 4, Informative

      Agree 100%, the overlap is tiny.

      The Pi has a keyboard, video output and a lot more CPU power. It will be used for projects where that's important.

      The Arduino does hobby electronics much better/easier/cheaper than the Pi.

      --
      No sig today...
  11. Alternate AVR Runtime by evildeece · · Score: 3, Informative

    I got fed up with it too, thats why I started MHVLib, a runtime for AVRs that doesn't try and hide its nature. My design philosophy is that embedded controllers are low on resources, and the runtime should be as lean as possible. http://www.makehackvoid.com/project/MHVLib