"d.tools uses OpenSoundControl messages to address hardware"
"your Arduino board is now a PC-controlled sensor data acquisition interface."
http://hci.stanford.edu/dtools/arduino.html


> access to usb memory sticks for arduino.
Very nice! Now I only need to find someone who is willing to do all this work for me.

I have the feeling that this is what eighthave is already doing with his Puredata/Firmata project.
Am I right?

Well, what I'd like to see in addition to the above is the functionality of the DataQ thing I mentioned earlier. A bunch of analog inputs so I can hook up all kinds of sensors, like for example variable resistors, industrial grade pressure transducers, temperature sensors, 4-20mA current loop and 0-5V devices, that kind of stuff.

The serial output could be something like this:
timestamp, analog in 0, analog in 1,... digital in 0, digital in 1, digital in 2, ...digital out 0, digital out 1, digital out 2...

> Here is a simple sketch

DId you hear that? he said "simple"!  

Thanks, that's a start. Although I have to admit I have no clue what is going on in that sketch, and this clearly shows me that this project is way over my head.  :-?
I hope more people will contribute so this project will eventually succeed!

This proposal could make the Arduino an interesting item for many more people without programming knowledge.

Very often the need arises to continuously measure some analog or digital sensors over extended periods of time, record the data on your computer, and switch something on and off. Professional data acquisition equipment capable of doing this can cost quite some money, usually too much for the poor engineering student or amateur doing stuff in his/her basement. That's why I want to propose a sketch which converts Arduino and a computer into a cheap data logger and digital I/O board e.g. for home automation, test equipment, artsy stuff etc.
A relatively cheap commercial product is the DataQ DI-194RS Data Logger Starter Kit for $24.95:
http://www.dataq.com/products/startkit/di194rs.htm

Unfortunately it costs over 50 Euros here in Europe, and it doesn't have any digital I/O functionality.

What I imagine is the Arduino continuously sending some sort of timestamp, the measured values of its analog inputs and the state of its digital ports to the computer every second or so, and maybe wait for commands from the computer in between so you can switch some relays or similar connected to some of the digital outputs on and off.  This would be a great addition and I'm sure many people would like to own such a device for little money, without having to program all that functionality for themselves.

Apparently this can be done easily with the MAKE controller, another microcontroller board which unfortunately costs $150. It can also communicate with Processing and Ruby using OSC (Open Sound Control).
"OSC is not a computer programming language, but is rather a (slightly obscure) communications protocol that is apparently known by many multimedia-oriented musicians."
Someone even built a LabVIEW interface for it. Very nice!

http://www.evilmadscientist.com/article.php/labviewosc

I guess it is too much to ask for anything like that.
Unfortunately my knowledge is too limited to try this myself. Has anyone already written such a sketch? Anyone willing to write one?

Do the boards work with different sketches? When you take the Atmega8 from your old Arduino board and insert it into the new ones, does everything work as before?
Dunno about possible software issues.
If it's an important deadline, maybe some nice person can send you two Atmega8 with bootloaders?

For basic experimentation you need a few LEDs, resistors, potentiometers, a few transistors, diodes, relays, switches. A breadboard, of course! Some perfboard to solder stuff.
You can hook up all of the usual robotics sensors to the arduino, so get what you think you need (e.g. Sharp range sensors).

> I'm connecting through a cheap Chinese 150 foot USB cable that I know to be
> unreliable in electrically noisy environments.

The USB specification demands cable lenghts of 3 to 5 meters max if I remember correctly. Even when chaining hubs or using line extenders the maximum specified cable lenght is well below 150 feet due to signal propagation delays. That's like running standard ethernet over a 200 meter long CAT5 cable.

Don't know what you plan to do with your arduino, but you might find this project interesting:

http://home.arcor.de/d_meissner/d_logg2_engl.htm
http://members.aon.at/w.walter/page_4_1.html
http://sprut.de/electronic/soft/skyplot.htm

Does that mean the current NG boards can be modified by soldering some pin headers/jumpers to the X3 area next to the USB port?

Being in a similar situation as you are, I found todbot's spooky arduino class very helpful. Have a look at the class notes 1-4 on this page.

http://todbot.com/blog/spookyarduino/

Of course there are more tutorials out there, but this one will get you started.

Peltier devices, also known as thermoelectric (TE) modules, are small
solid-state devices that function as heat pumps. A "typical" unit is a few
millimeters thick by a few millimeters to a few centimeters square. It is
a sandwich formed by two ceramic plates with an array of small Bismuth
Telluride cubes ("couples") in between. When a DC current is applied heat
is moved from one side of the device to the other - where it must be removed
with a heatsink. The "cold" side is commonly used to cool an electronic
device such as a microprocessor or a photodetector. If the current is
reversed the device makes an excellent heater.

As with any device, TE modules work best when applied properly. They are not
meant to serve as room air conditioners. They are best suited to smaller
cooling applications, although they are used in applications as large as
portable picnic-type coolers. They can be stacked to achieve lower
temperatures, although reaching cryogenic temperatures would require great care.
They are not very "efficient" and can draw amps of power. This disadvantage is
more than offset by the advantages of no moving parts, no Freon refrigerant, no
noise, no vibration, very small size, long life, capability of precision
temperature control, etc.

Taken from http://www.peltier-info.com/info.html

On page 40 of this pdf there is the schematics for connecting a relay to the arduino.

http://todbot.com/blog/wp-content/uploads/2006/10/arduino_spooky_projects_class4.pdf

If your project involves Antarctica you could use a peltier element to create a cold or hot metal plate on demand. A peltier element creates heat on one side and gets cold on the other when electricity is applied.
The easiest way to heat a metal plate is probably placing a light bulb behind it, but that will only allow slow heating of the plate.
Or you could circulate ice water and warm water behind the metal plates, switching between the two with an electrically operated (solenoid) valve. I prefer the warm/cold water idea due to its instantaneous response.

> as your code changes length, this would alter  the PWM signal.

True. I guess it depends on what you want to do with it. It won't work for precision stuff, but it might work sufficiently well for dimming a bunch of LEDs...

Isn't it possible to code your own PWM?

reading - writing multiple pins simultaneously
http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1160606668