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4636  Using Arduino / Project Guidance / Re: Hi speed video camera on: September 17, 2013, 12:12:48 pm
like i say id be happy with 3seconds of 1000fps at hd quality

but not gonna happen it would seem

Some smartphones are heading in that direction (the A7 will capture over 100 fps if I remember correctly although I don't think it does HD at that frame rate), although I think it'll be a fair while before we'll see 1000 fps. But using a cheap little microcontroller to do bleeding-edge video capture is rather ambitious, to put it mildly.
4637  Using Arduino / Programming Questions / Re: Track minutes per day a valve is on on: September 17, 2013, 11:09:43 am
The arduino controls the valve, so pin 2 is an output.

That's incorrect - the sketch contains no code that controls the valve. Pin 2 is used as an input in this sketch. If that's not what's happening in your real project then you need to step back and ask your question again, this time using code that demonstrates the actual problem.
4638  Using Arduino / Programming Questions / Re: How to send digital output data to the onboard webserver?? on: September 17, 2013, 11:06:40 am
The Dallas code you have got reads the temperature from a sensor, and then prints a message including that temperature to the hardware serial port.

You want to produce some similar code which reads the temperature and then prints a message including the temperature to your network client object.

The code reading the temperature is:

float tempC = sensors.getTempC(deviceAddress);

I don't think the Ethernet Client class supports printing float values directly, but as a starting point you could convert the value to an integer and print that:

client.print("Temperature is ");
client.print((int) sensors.getTempC(deviceAddress));
client.println(" C<br />");

To get a floating point output you would need to convert the float value to a string and then use client.print() to include that string in the response.
4639  Using Arduino / Programming Questions / Re: Reattach interrupt doesn't working on: September 17, 2013, 10:59:07 am
I cant use micros because I have to measure the time between two FALLING edges.

You'll have to explain that one a bit more - I can't follow your reasoning.
4640  Using Arduino / Programming Questions / Re: Controlling Servos on: September 17, 2013, 10:58:18 am
Making something flap like a bird is entirely feasible.

Making it capable of flying is massively harder and I suggest you abandon any thought that the static flapping model powered by servos will ever actually fly.
4641  Using Arduino / Project Guidance / Re: help needed asap on: September 17, 2013, 10:51:35 am
Yes. You are right. Already I read about videoExperimenter shield. And I observed the LM1881 IC on that shield. But now I have this IC separately. So my question is, Can I using this IC and get the signal then send it to my Arduino for processing is possible or not? And is it possible to process when I don't using videoExperimenter shield? Please give some suggestions asap.   

Almost anything is possible if you're willing to throw enough time and money at it. Whether you can do it is another matter. If you want to do something similar to the video experimenter board without using the board then you need to understand what it does and how it does it, and be capable of developing something similar. Do you and are you?
4642  Using Arduino / Project Guidance / Re: Looking for a code to check if bluetooth is paired or not on: September 17, 2013, 10:48:29 am
I'm not familiar with that device but Google suggests that it provides a text-based command interface so I suggest you review the command syntax and see whether there are any commands to report the connectivity status.

Alternatively, you may find that it can be inferred from the RTS/CTS outputs.

You also have the option of using a keepalive so that you get positive confirmation when the adapter is paired and successfully communicating.
4643  Using Arduino / Project Guidance / Re: Controlling DC motor (2 directions) with 4 transistors? on: September 17, 2013, 10:37:20 am
What you're trying to achieve would be a H-bridge circuit. You can buy Arduino shields and compatible boards providing this, but there's no reason not to make your own if you want to tackle the electronics yourself. I can't tell whether the circuit shown in your picture is correct, but you could Google H-bridge driver circuit to see how it's supposed to look, and also look for the circuit diagram for standard H-bridge drivers (I guess there will be some published schematics somewhere).

Also measure the voltage drop across each of your transistors when it is supposed to be fully 'on' and compare that against the expected forward voltage drop for that transistor type - it may be that you are using an unsuitable transistor type, or not turning it fully on.
4644  Using Arduino / Project Guidance / Re: Hi speed video camera on: September 17, 2013, 10:32:51 am
It might be cheaper to use the "bullet time" approach and just use a separate camera per frame, triggering them all from a central controller. This seems like an expensive approach too, but it might still work out cheaper than spending tens of thousands of pounds on a really, really fast high commercial camera.
4645  Using Arduino / Project Guidance / Re: Ultrasonic dist. meter reading water level? on: September 17, 2013, 10:27:00 am
I've read that it works more reliably if you bounce the pulse off a float with a smooth reflective top surface, rather than trying to detect the water surface directly.

And, you need to get rid of the duplicate thread you started.
4646  Using Arduino / Project Guidance / Re: File transfer from SD card to website via GSM modem on: September 17, 2013, 08:31:55 am
What I'd like to be able to do is take a file from the SD card and upload it straight to a website using the modem. To be honest, I'm hoping there's a library out there that someone's already written to do this! I've seen a few posts on this forum that relate to this, but I've yet to find anyone who's publicly documented a solution.

I think that what you need to do is use extended AT commands to initiate an HTTP connection and then carry out an HTTP request that uploads the file content. There are a couple of ways you can do that in HTTP. I suggest you start by implementing the web server part that presents a page you can use to upload the file interactively. Use Wireshark to see what HTTP request actually goes over the wire when you upload the file. Then modify your sketch to send a similar HTTP request (via the AT extended interface), changing parameters like data length and content as required.

You should find an example with the GSM library that demonstrates how to use the AT extended interface to send an HTTP request and read back the response.
4647  Using Arduino / Programming Questions / Re: Serial Call and Response (handshaking) with ASCII-encoded output help on: September 17, 2013, 08:26:46 am
I was getting the error message: Cannot find anything named "Serial"

Where are you getting this error - is it when building the Arduino sketch, or the Processing application?
4648  Using Arduino / Programming Questions / Re: Works there but not here :( Anyone see why ???? on: September 17, 2013, 08:22:31 am
The code you posted is incomplete.
4649  Using Arduino / Programming Questions / Re: Track minutes per day a valve is on on: September 17, 2013, 08:17:56 am
I'd like to know if anyone has a simpler way.

Poll the state of the valve as frequently as you like. Remember the previous state, and compare with the new state to see whether the state has changed. There is an example sketch demonstrating this 'edge detection' logic. I recommend including some debounce logic so you don't get multiple triggers when the valve is moving (there are example sketches demonstrating this, too).

If the valve state changes from OFF to ON then record the current time in a variable.
If the valve state changes from ON to OFF then subtract the 'on' time you recorded earlier from the current time to get the elapsed time it was on for. Add this to an accumulator.

Use the logic PaulS mentioned to reset the accumulator and restart timing at midnight.
4650  Using Arduino / Programming Questions / Re: Alternative to millis() on: September 17, 2013, 08:10:04 am
By my reckoning, nine hours is about how long it would take to overflow a signed int that was being incremented once a second. If that's the technique you're using for counting the passage of time, you're doing it wrong.
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