Hi all,
Are there any kits which are dual core/ quad core arduino? Where can I buy it?
Sorry for not answering your question; but why do you need it? 
Just thought of doing parallelism to increase the performance and asked to know whether it is available or not.
They are not currently available as mass produced boards (as far as I know) but there are a lot of people who have made their own... I did some designs a few months back but never got round to producing them...
Mowcius
http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1205243372/all
[edit]About the increase in performance...
First figure out how many percent of your program can be done in paralell. Then divide that, by the number of cores.
There you have the amount of % performance gain.
Oftentimes, at the cost of readability, predictability and extensibility. ::)[/edit]
Using a floating point co-processor is another form of parallelism.
I've been thinking about multicore Arduino a bit because my board is stackable -- you should be able to just stack them on top of each other like shields and then clip the stacking header pins for any pins you DONT want shared by each board (the TX/RX on the UART seems to be the obvious choice).
But the real question is why bother? I mean you can purchase a cheap small form factor x86 (around 1GHz) motherboard for $50+. So say $70 with lots of memory. It would take 50 Arduinos to approach this speed. Of course, a PC does not have the GPIOs as the Arduino. So it seems to me that the real solution is to hook an Arduino up to the PC via the USB and so essentially turn the Arduino into a GeekPort for the x86.
Really, the only reason d'etre I could come up with for multi-core Arduinos would be to use each one as a special purpose device to handle a subset of your total problem. For example, one could handle button/sensor input, another sound output, another drive LEDs or an LED matrix, etc. On a normal processor each job would be handled in a separate thread. In the Arduino environment each job is handled by a separate uC -- "physical threading" would be a good term for it I guess. And the advantage is that you basically guarantee that no job can interfere with any other job since they each have dedicated processors. On a threaded system this potential interference is a very big issue that is almost impossible to analyze.
The most famous bug caused by thread contention that I can remember was the one that shut down the original mars rover...
Now if we paved a PCB with an array of FPGAs then THAT could seriously compete against the high clock rates of COTS boards for certain problem sets :-).
What kind of application do you have in mind?
going from a arduino to a 1ghz pc or a slab of fpga's is abit of a jump
My "other" mcu is the ubw32 which sports a 80mhz 32bit mips core pic, Atmel makes their version of it too, either way these are pretty zippy chips, with tons of I/O.
Of course, a PC does not have the GPIOs as the Arduino
See this:
http://www.trossenrobotics.com/roboard.aspx?a=blog
@florinc: Nice!
@Osgeld: My point was simply that before you go to multi-core Arduino, go to a faster chipset. I chose to highlight an architecture with the fastest chipset for under a typical hobbiest budget of $100. But I agree, there's lots of good embedded choices in between. Although it is interesting to note that they often cost more than a standard PC because of the lack of volume, or maybe because the market will bear it; the dev kits are targeted at embedded development companies which can spend $400-$1k for a single board without blinking an eye.
@florinc: Nice!
@Osgeld: My point was simply that before you go to multi-core Arduino, go to a faster chipset. I chose to highlight an architecture with the fastest chipset for under a typical hobbiest budget of $100. But I agree, there's lots of good embedded choices in between. Although it is interesting to note that they often cost more than a standard PC because of the lack of volume, or maybe because the market will bear it; the dev kits are targeted at embedded development companies which can spend $400-$1k for a single board without blinking an eye.