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1  Using Arduino / Project Guidance / Re: post picture to twitter via arduino on: Today at 12:45:53 pm
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and how much time would it take it from the time the picture is taken to its transfer to the SDcard
Click your link. Read how many bytes per picture. Divide by 512 to determine the number of writes to the SD card.

Measure how long a write takes. flush() forces the dump of the buffer to the card, even if the buffer isn't full. A nearly full or nearly empty buffer makes almost no difference

A little multiplication and division, and you can determine the answer yourself.

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and then uploaded to twitter through the wifi shield.
You'll need to measure that yourself. There is no hard and fast answer. It depends on your network. But, it will not be fast.

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I think this can be done
So do a lot of other people. The number that can actually make it happen is a small fraction of those that think it is possible.
2  Using Arduino / Project Guidance / Re: Modifying a variable frequency pulse? on: Today at 12:39:14 pm
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The challenge is that the output isn't consistent and is constantly changing.
It's consistent between readings, isn't it?

How do you plan to output n pulses per second? Or n * m pulses per second?
3  Using Arduino / Networking, Protocols, and Devices / Re: GET function not working as expected. PHP setting issue. on: Today at 12:35:09 pm
Code:
      client.print("GET http://suyogtechnologies.com/testing.php?arr=");
      client.print(currentMillis); 
      client.print("arr1=1234"); //just a testing variable   
      client.println("HTTP/1.1");   
The script to execute is NOT http://suyogtechnologies.com/testing.php. http is the protocol to use to talk to the server. The server has already been defined.

The GET request as you send it is "GET http://suyogtechnologies.com/testing.php?arr=XXXXarr1=1234HTTP/1.1" which is utter nonsense. Get rid of the http://suyogtechnologies.com./ bit. Put an & between arr=XXXX and arr1=1234. Put a space before the HTTP/1.1 part.
4  Using Arduino / Programming Questions / Re: How to detect frequency on: Today at 12:24:42 pm
Don't you suppose that the time between two highs would define the period?
5  Using Arduino / Programming Questions / Re: Serial.read - How to parse serial input without delimiters on: Today at 10:43:45 am
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This is a bit over the top for me at the moment.
Why? Read the serial data. If you read a 'Z', you are in the "GotAZ" state, where you do something different.

In the GotAZ state, read the first character available. If you get a D, you are in the GotAZandAD state. If not, you return to the LookingForZ state.

In the GotAZAndAD state, read when there is data, until you've read 22 more characters.

Engage your brain!
6  Using Arduino / Programming Questions / Re: Looking for general code to read from Serial port and return char* on: Today at 10:38:47 am
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Oh so I should create a generic global variable of size 512 for ALL data coming from the Xbee module?
I think you should explain why an XBee is sending you a mini novel. Why can't you read and process the data in smaller chunks?
7  Using Arduino / Programming Questions / Re: Looking for general code to read from Serial port and return char* on: Today at 10:31:43 am
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and the space is immediately available.
While the pointer points to space that may be overwritten at any time, there is nothing that says that this does happen. On the other hand, there is nothing to say it doesn't. What you are doing is relying on it not happening, which is a poor programming practice.

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Am I not copying the pointer?
No. You are copying the data from the memory location that the pointer points to. It is that memory that can be overwritten at any time - like the next time a function is called. It's hard to call memcpy() without calling a function.
8  Using Arduino / Networking, Protocols, and Devices / Re: <Help ME! Please> How to send String from my arduino Uno to vb6 on: Today at 10:26:40 am
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i had wrote my code in arduino and it's work if i look from serial monitor.
So, the Arduino is doing what it's supposed to.

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But when i look with vb program, the string was sent per digit and can show full of word.
I recognize all the collections of letters as being valid words. The collection of words conveys no meaning, though.

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Is there anybody kind help me, please?
Without seeing your code? No.
9  Using Arduino / Project Guidance / Re: Overloaded data-logger. on: Today at 10:20:52 am
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similarly, when it takes 80ms for the pulseIn() function to return something it just have to put up with it.
No. You could use the NewPing library, which uses interrupts to provide non-blocking behavior.
10  Using Arduino / Project Guidance / Re: RFID triangulation feasability on: Today at 09:31:17 am
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It's not that hard to find 50m RFID cards on the web.
They are actually fairly common as far as i can see.
Sure, but the readers are damned expensive.

Another issue with RFID readers is that they generally read a tag ONCE when it comes in range, and do not send any information when the card goes out of range. I don't think that RFID is going to suit your needs.

And, unless you got three different kinds of readers that read three different kinds of cards, you will have interference.
11  Using Arduino / Project Guidance / Re: Small led display with power timer on: Today at 09:27:30 am
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1. What is the best way to implement this very simple function of turning off?
A switch that physically disconnects the power source.

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Wich library?
I like the Maple Valley library. It has more books than the Black Diamond library.

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2. Are they an arduino better for this kind of stuff?
They are all the same - disconnect power and they stop running. Restore power and they resume working.

12  Using Arduino / Project Guidance / Re: Problem with ethernet sheild please help! on: Today at 09:23:56 am
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Ethernet shields are finicky.
Correct. They do not like being used by dumbasses that can't read and follow directions.
13  Using Arduino / Programming Questions / Re: Looking for general code to read from Serial port and return char* on: Today at 09:19:48 am
Code:
  memcpy(newChar, got , 25);
got points to the stack. At this point, it is pointing to garbage.

Code:
  free(got);
Freeing a pointer to memory you didn't allocate. is a great way to corrupt memory.

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I would like to receive strings small and large with Readxbee function.
You need to decide what defines a large string, and pass an array of that size to the function. Have it return a value indicating whether the array contains all the data, or not.

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However, I would still need the function to at least be able to read 512.
Re-write the sender to be less chatty.
14  Using Arduino / Programming Questions / Re: I am receiving error with unusual characters using Adafruit Wifi shield on: Today at 09:14:20 am
Without the USB cable, and the serial output, how do you know that the output changes?
15  Using Arduino / Networking, Protocols, and Devices / Re: GET function not working as expected. PHP setting issue. on: Today at 09:08:19 am
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Any guidance will be appreciated!
Post ALL of your code.
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