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3706  Using Arduino / Project Guidance / Re: Anyone know a USB keyboard library for Arduino UNO? on: August 05, 2013, 03:56:33 pm
if you still want to use the UNO.. you'll need a USB host shield..  smiley

According to that link the question is how to make the Arduino emulate a keyboard, not how to make it receive events from a keyboard.

There are plenty of examples on the internet of people who have used an Arduino to emulate a keyboard, including some that were implemented on a UNO.
3707  Using Arduino / Project Guidance / Re: air flow sensor on: August 05, 2013, 03:53:53 pm
UPDATE: Jack hit it on the nose - medical hobby project. The person will take a deep breath, blow as hard as they can and measure the peak flow.

Probably the easiest solution to make reliable would be to measure the static pressure drop in a venturi. You could size the venturi to suit your accuracy requirements and the resolution of your pressure sensor.
3708  Using Arduino / Programming Questions / Re: help needed for changing the speed of a continuous servo on: August 05, 2013, 08:08:41 am
It depends on, if the servo is Analog or Digital ...

It certainly should be possible to control the speed for 'continuous rotation servos' made from analog servos. I'm not sure why you'd want to butcher a digital servo for continuous rotation (it seems to negate the main benefit of the digital controller) but even if you did it would still provide a proportional feedback which I would expect to provide proportional speed control.
3709  Using Arduino / Programming Questions / Re: servo programming on: August 05, 2013, 05:44:23 am
Check whether your servo can actually provide a full 180 degree rotation - not all servos can.
3710  Using Arduino / Programming Questions / Re: Is there a sample GUI program in Java to Arduino? on: August 05, 2013, 05:42:37 am
Look at Processing - it is essentially Java, provides a simple user interface and can easily be used to communicate with an Arduino.
3711  Using Arduino / Programming Questions / Re: help needed for changing the speed of a continuous servo on: August 05, 2013, 05:39:38 am
You cannot control the speed per-se on a servo modified for continous rotation.

Yes, you can. For each server there will be a pulse length corresponding to the neutral position. When you send this pulse length the servo will not move. Altering the pulse length either side of that value will cause the servo to move forward or backwards, and the further away you go from that neutral value the greater the speed (until you reach the servo's maximum speed).
3712  Using Arduino / Programming Questions / Re: What functions interfere with EEPROM read/write? on: August 05, 2013, 05:35:38 am
Suggest you post a minimal sketch which demonstrates the problem, for example by writing a sequence of hard-coded values to the EEPROM and displaying the values read back. It may be a hardware problem, but it may simply be a problem with your code.
3713  Using Arduino / Programming Questions / Re: Usb to serial diy converter on: August 04, 2013, 05:58:26 pm
Anything with a d-sub connector is probably using RS232 signaling and would need to be converted to TTL serial signaling before it is safe to connect to your Arduino.

There are readily available and inexpensive USB-to-TTL-serial converters which do exactly what you need - most hobby sites that offer Arduino hardware and clones will offer something suitable, and they only cost a few bucks. The only gotcha is to ensure that the TTL voltage level of the converter matches the voltage of your board i.e. 3.3V or 5V.

ETA: or in other words, what Majenko said.
3714  Using Arduino / Project Guidance / Re: Whistle detection-pressure cooker on: August 04, 2013, 05:53:18 pm
I don't know how much of the project you're describing is specified for you and how much constitutes part of the solution that you have designed.

If the person specifying this is intending that it does something that could credibly be useful to a cook, I'd suggest that monitoring the temperature would be the most useful thing to do. Zoomcat's idea of using an IR thermometer might be your best bet, although in my experience pressure cookers tend to be shiny metal and that's not a good target for an IR thermometer. So it would be quite hard to do in general, but if you can control the test conditions then it should be possible to get something to work. If you're willing to put something in contact with the lid of the cooker then things get much easier, and you also have the possibility of implementing an over-temperature alarm (aka your pressure cooker has run out of water and is about to be destroyed).
3715  Using Arduino / Project Guidance / Re: Ethernet with SD card Shield - Compiling larger scripts. on: August 04, 2013, 05:46:05 pm
Well, I know you can load html pages on the SD card support for the Arduino, but what I'm saying is, if I need to compile anything directly such as giving the Arduino SSH or FTP support so I can tunnel in and move what I need to do.

I do a lot of embedded work professionally with PLC's and SCADA networks.

What I'm wanting to know is if I can compile something on the SD card if I were to use it as its ROM, so I could essentially compile and load an embedded linux kernel, or does the ethernet shield contain the a piggy-back processor that takes care of HTML instructions and the sort?

No, none of that makes any sense at all in the context of an Arduino. You can't compile any new Arduino features on the Arduino, and it's a few orders of magnitude short of being able to do anything with or to a Linux kernel. I don't know what HTML "instructions" you're thinking of, but the Ethernet shield has no knowledge of HTML, HTTP or anything of that sort - it just handles the transport layer and the protocol layers below that. The Arduino is a microcontroller, not a computer. If you want an embedded computer, you should be looking at a RPi or one of the other embedded computer platforms.
3716  Using Arduino / Programming Questions / Re: Serial Proxy that runs on a Arduino. Does it exist already? on: August 04, 2013, 06:56:34 am
If you're dealing with a CNC solution this implies a considerable investment of time and money - it seems odd to me that a few bucks difference in the cost of a different Arduino model would be a factor. If this is to be a product, it seems odd to me that you'd be wanting to use a standard Arduino at all.
3717  Using Arduino / Programming Questions / Re: How do I get an Arduino to initiate a UDP session? on: August 04, 2013, 06:53:04 am
There is no such thing as a UDP "session".

On the network side, that's true. But on the API side some of the semantics of a session do apply, for example in Posix you can bind a datagram socket to an address. While it doesn't establish a transport connection, it establishes a state within the client that has a similar effect at the API level.
3718  Using Arduino / Project Guidance / Re: Detecting lean angle on a motorcycle on: August 04, 2013, 06:47:12 am

Isn't that why bikers have knees?
3719  Using Arduino / Project Guidance / Re: Indoor tracking device on: August 04, 2013, 06:44:06 am
If there are people around the machines you want to track then one option is to install a siren which can be triggered remotely. If you're near by, you may be able to hear it directly. If you aren't, there may be other people nearby who can hear it and contact you to turn that damned noise off. Perhaps you could combine that with some sort of intercom mounted on the vehicle which people could use to contact you. If it worked, this might have a knock-on effect that people would be reluctant to have these machines left in their work area because of the nuisance factor when the siren goes off. That might be a good thing.
3720  Using Arduino / Project Guidance / Re: Ver...y long range communication on: August 04, 2013, 06:35:59 am
You may be overstating the requirements. Do you really need a wireless connection over 200 miles range? I can't see why you would need that unless your woodlands were 200 miles across, which seems unlikely.

Depending what your true requirements are, it may be that you can get away with a wireless connection with a much shorter range to a base station which has internet or phone connectivity (wired/wireless). It would be much easier to achieve this from a fixed base station than from a mobile device because you can use directional antenna to increase the wireless range, even if you can't manage to set up a wired connection. Depending on the size of antenna you're able to use at a base station and the area you need to cover, you may need multiple base stations. However you achieve it, once you have got a path back to a land line or cell tower, the rest is easy.
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