Gertboard expands the Raspberry Pi’s GPIO pins

http://www.raspberrypi.org/archives/1734

by wiradikusuma • 14 years ago

88 41 14 years ago

raspberrypi.org

option_greek• 14 years ago

I was really looking forward for something like this. I hoped the price would be a bit low though.

wiradikusuma3• 14 years ago

Probably this link can help http://elinux.org/RPi_Expansion_Boards

What I'm looking for is a step-by-step field guide for "interacting with real world" for programmers with zero experience in electrical engineering.

franzus2• 14 years ago

Yeah, I know what you mean. There's not much information about "electronics for software guys". Every resource I could find was "the other way around": Programming for electronics guys.

There were some promising videos on youtube but it all boiled down to: "Here's this simple circuit. <no explanation about the circuit> Now to the hard part: FOR loops. <30 minutes about for loops and basics of C syntax>".

I guess this would be a great topic for the pragprog-guys. If they'd commission such a book I'd buy a dozen copies ;)

jiggy2011• 14 years ago

What you need is "electronics engineering" not "electrical engineering". Electrical engineering means building things that can handle huge currents, not something you want to do with "zero experience". :)

willyt• 14 years ago

microchipc.com was a great resource when I was learning to use pic microcontrollers.

FrojoS• 14 years ago

> Gertboard is packaged as a kit. It doesn’t come preassembled; you will have to solder it together yourself.

I hope it won't take to long until there will be pre-assembled ones, too. For an open source design, all you need is someone who invests some money to get the board assembled in China and then sells it in a web store.

Here is an example, to show how affordable assembling low quantities of boards in China has become. For one of our designs, buying all the parts online in the US or Switzerland, was about $150. If you buy about a dozen of them in China, they are about the same price point. But then, they are already assembled according to our design! Once you buy around one hundred, you save considerable money. In our case, the offer we got is about $100 per board (33% savings!).

The lower the transaction cost, the better. If you think soldering has minimal transaction cost, compare the price of a soldering station with a Raspberry Pi.

LiveTheDream• 14 years ago

That is quite a savings. The Chinese-assembled boards can have a defect rate of up to 50% and still be competitive with the original price (ignoring time lost and extra shipping charges).

jberryman2• 14 years ago

Not to contradict your point, but this board should be easy to assemble as a first project with an investment in <$20 of soldering equipment and supplies. So I'd encourage anyone who's interested in this but new to electronics to head over to sparkfun and just dive in and see how you like it.

veemjeem6• 14 years ago

Easy? Not so... this is not a beginner's kit, there are surface mount components, and if this is your first time soldering, it's gonna be a rough day.

Sparkfun does a really good job of making their kits easy. If you look closely at them, the boards that require diodes and electrolytic capacitors have a picture printed on the pcb that make it really obvious what the polarity is. The gertboard pcb doesn't have any of these. If you solder a led backwards, you're SOL. So if you haven't seen a diode or led before, you probably shouldn't pick the gertboard as a first project.

You can buy the arduino as a kit, but most people who are just starting out with electronics will get one prebuilt so they don't accidentally stick their atmega chip in backwards.

georgeecollins• 14 years ago

While I think this is cool, I am not really sure what the advantage is of this over a bunch of micro controller cards that you can connect with a USB. There are a lot of different ones available and you can get them per-assembled or as kits.

If you are waiting for this to control things with your Raspberry PI, I think some choices already exist.

For example: http://www.societyofrobots.com/axon_select.shtml http://adafruit.com/products/849 http://www.parallax.com/Store/Microcontrollers/PropellerDeve... http://www.parallax.com/Store/Accessories/MotorServoControll... http://www.parallax.com/Store/Microcontrollers/PropellerDeve...

That's just a fraction of what is out there. And to repeat, I think the gertboard is cool. But if you are waiting on it to control things, you don't have to.

sean-duffy• 14 years ago

To be honest, I think if you're a programmer/developer looking at the Raspberry Pi as a gateway to basic electronics, you'd barking up the wrong tree and would be better off with one of the Arduino boards. With the Arduino you have plenty of resources, and the convenience of only needing the Arduino IDE and a USB cable to upload your program to the micro-controller. The Arduino platform can do a lot in terms of reading sensors and controlling circuits, and if that's all you want to do then a Raspberry Pi is far more than you actually need, and much more expensive than an Arduino too.

veemjeem6• 14 years ago

If you were a programmer, it seems like the RPi would be a better choice than the arduino -- you can code in the language of your choice instead of processing or C, and you can still control interface pins to the outside world.

Also, you'd probably do more with the Pi as a programmer beyond turning pins on/off -- for example, you could hook up a camera and run opencv, then write a small app to control a water gun that shoots squirrels off your bird feeding post.

When you start doing more with arduino, you typically want network connectivity, and most of the wifi/ethernet shields for the arduino are the cost of the entire RPi computer. I think the RPi does fill a good niche in the hardware world.

ricardobeat• 14 years ago

Just get a teensy[1] board, and hook it up to the Rasperry Pi.

I'd like to know what kind of stuff you can do with the GPIO pins directly on the Pi, via /sys/class/gpio. Are they just digital (0,1) or they can read voltage levels too? (electronics newbie here)

[1] www.pjrc.com/teensy/

veemjeem6• 14 years ago

they are just digital (0,1). you need a A/D converter if you want to read analog signals.

Here's a tutorial on hooking the raspberry pi with one of those chips to give you analog input: http://learn.adafruit.com/reading-a-analog-in-and-controllin...

beardicus• 14 years ago

Arduino's are usually $30, though you can get the clones for $20. The ethernet shield alone is $45. The cheapest Arduino-a-like with built-in ethernet, as far as I've found, is the Nanode v5, at $40 in unassembled kit form.

http://wickeddevice.com/index.php?main_page=product_info&...

Many of your other points are valid. For tons of projects a Pi would be overly complicated overkill, but I can think of many times when I'd want more video in/out capabilities, plus the ability to blink some lights, drive some motors, and accept non-usb sensory input.

jws• 14 years ago

If you want to be network accessible, the Raspberry Pi costs about the same as an Arduino with an ethernet added.

As far as programming, simple is easy on Arduino. The limits are further away with a Raspberry Pi. Say you want to log some data for later analysis. Trivial on a Pi. Anything more than a few kilobytes and you are wiring an SD card to your Arduino.

I'm currently using Arduinos for well defined, simple functions, but for more complicated functions. I will use Raspberry Pis where the BeagleBone CPU is overkill, but Arduino will always win for low power use.

rlpb• 14 years ago

I really like the idea of the controller being a familiar environment with a high level programming language. I'm sure that Arduino can do all the same stuff, but it seems like the learning curve is far steeper.

medinismo2• 14 years ago

has anyone bought/read/use the paraprog guide for raspberry py at pragprog.com/book/msraspi/raspberry-pi? I would like to get started and this book seems to be the only viable starting guide

veemjeem6• 14 years ago

I don't think you need a book to learn how to use a computer. You just plug it in and go.

alexchamberlain• 14 years ago

Have you seen some of the questions we are getting at http://raspberrypi.stackexchange.com/?

StavrosK• 14 years ago

This is semi-offtopic, but has anyone found a good powered USB hub on dx.com, that can power the RPi and peripherals? I'm tired if it not having enough power to run wifi, or mobile internet, or anything else I put on there.

I'm in Greece, so dx is pretty much the only site that will ship cheap stuff to me, but if anyone has another recommendation for a good hub, I'm thankful.

Gertboard expands the Raspberry Pi’s GPIO pins

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