Quote from psergiu on November 8, 2011, 14:08
I believe that a lot of people will want to use the RPi as an Arduino replacement for "blinking lights" and other low-level & low-speed projects.
Yes, that is what I want to enable.
IMHO, the easiest system to use is a plug straight into a breadboard.
Something like this IDC DIL Connectors
If all the RPi's connectivity options will be "by professionals for professionals" - a lot of people will give up trying their first "blink a led" project.
Agree, and I'd like folks to be able to do those experiments easily.
If the Arduino people do intend to standardize on a new, better pinout for shields, indeed let's talk to them and find some common ground (and GND pins
We should try. But an R-Pi is so electrically different that they may quite reasonably feel we are over constraining them.
Example of some compatible Arduino shields (3.3v capable, do not require pwm or analog pins) i found in a couple of minutes:
W5100-based ethernet shields use only the SPI & digital pins and are 3.3v
This is exactly an example which I feel is of low value. Hence why I asked for a list of things that "... provide something that RaspberryPi does not have already ".
R-Pi already has ethernet, and drivers, integrated into the system.
I agree some people might want a second ethernet, but I'm not convinced an arduino shield will be popular enough to justify constraining a breakout to the Arduino pinout for it.
It might be much better to use a second R-Pi and talk over USB or SPI anyway.
GSM Shield - http://www.sparkfun.com/products/9607
Yes, the same module is on a breakout module too:
for $40 less, i.e. you could have a free RaspeberryPi.
Making a breadboard friendly breakout board on 0.1" is probably more popular than making Arduino shields.
Lots of other ready-made shields could work allowing soldering-shy people to do cool stuff with their RPis. Not everybody was born with the soldering iron in their hands. The RPi is on track to become the new Apple II - we need something akin to the Apple II peripheral cards.
Apple II ignored the existing standards.
IMHO, their are a few problems constraining development to reuse poor 'standards'. Much better to use an existing, easy to use standard technology, along with an easy way for anyone to access a much larger set of electronics.
Using 0.1" pitch headers is already a very popular approach to making electronics available. 0.1" pitch connectors are popular for break out boards already. You can get *LOTS* of electronics that way. Far, far more than Arduino shields.
Constraining something which is much, much faster and more powerful than an Arduino to use a poor, DIY unfriendly standard almost destroys the ability to get much benefit.
IMHO, it would be better to use an ATmega to carry an Arduino pinout, and talk to it over USB (doable now). There is no hardware development needed to use USB, and all shields work. Job done. If the R-Pi retains serial, then an R-Pi Arduino shield adapter doesn't even need USB, and is cheaper than an Arduino. For now, you can prototype using an Arduino.
There are already through-hole PCB's designs so there is no hardware development needed. My chum Chris Godbert has designed a Serial Arduino PCB which can be made on common school milling machines for less than a £1, so a DIY serial-Arduino-shield-adapter would cost about £5 to make, one-off. Likely much cheaper than every alternative way of getting Arduino pinout compatibility.
Even cleverer, if the Arduino shield is 3.3V compatible, and only needs SPI and power (e.g. the ethernet shield), we could make a tiny SPI adapter from the R-Pi, plug it into the Arduino ISP header, and the shield adapter doesn't need anything else other than female headers. Job done,