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1  Using Arduino / Installation & Troubleshooting / Re: Upload stopt at 95% on: July 25, 2014, 11:15:29 pm
Turn on "Verbose Output" in the Preferences, and try again.
2  Using Arduino / Installation & Troubleshooting / Re: programmer is not responding arduino uno Mac OS X on: July 25, 2014, 11:14:47 pm
Quote
Code:
/dev/tty.usbmodem621
Looks right.

Which Arduino are you using?
3  Using Arduino / Project Guidance / Re: Digital Pin Commands on: July 21, 2014, 09:31:46 pm
One option would be to use a web server example.
4  Using Arduino / Project Guidance / Re: Digital Pin Commands on: July 21, 2014, 07:10:17 pm
How will the Android app communicate with the Arduino?
5  Using Arduino / General Electronics / Re: Arduino Due: Minimum reading of "20" on analog inputs on some PCBs on: July 21, 2014, 07:02:48 pm
I've attached the schematic for the PCB board having trouble. 
Yet, the PCB file is probably what we need to see, not the schematic.

Ideally the actual PCB file, not just a picture.  So we can take a good look at your ground planes.
6  Using Arduino / Project Guidance / Re: Arduino + Hue? on: July 20, 2014, 11:20:11 pm
I know that I need the wifi component, but can anyone point me in the right direction as to the basics of what I should purchase to get started on this?
If you want to access WiFi, you need a WiFi shield.  The Arduino's WiFi shield, while expensive, is nice because it takes care of all the communication, encryptions, and even provides a tcp stack.  Keeps the burden off of the smaller microcontrollers.

I've found many posts with bits and pieces of information, but no complete advice on which Arduino to buy.
You choose the Arduino based on the number of I/O you need, amount of RAM you want, what devices you'll interact with, etc.  So far, you have given no details other than "a physical object."  Makes it difficult to suggest a piece of hardware when you don't know what the hardware is expected to do.

I don't know if the starter kit would be the best choice for the project in mind which is to essentially control hue with a circuit
What circuit?  That's the missing piece of information.  Again, can't suggest what hardware to buy without details of what circuit you're trying to build.

(using their documented API : http://developers.meethue.com/).  As of now, I don't need help with the programming methods - just hardware choices.
The API looks very text/string heavy.   With only 2K-4K of RAM, this is going to be challenging (but not impossible) on most Arduino boards with their simple 8-bit microcontrollers.  It seems like a standalone device that needs to communicate with a web server would be a better project for a Pi, Beaglebone, or maybe the Galileo.

For example, there's a nice tutorial here http://arduino.cc/en/Tutorial/WiFiWebServer.
You want to make a webserver or you're using that as an example tutorial you'd like to find for the project you haven't described yet?   
7  Using Arduino / Project Guidance / Re: Arduino Programs on: July 20, 2014, 08:31:41 pm
It is an Uno.
Okay, so in 2K of RAM what games and applications are you going to run, through an interpreter, while driving a 2.8" LCD screen?
8  Using Arduino / Project Guidance / Re: Arduino + Hue? on: July 20, 2014, 11:01:24 am
Thanks but I think you can surmise from my post count that I already knew that.  
I wasn't responding to you, duh.
9  Using Arduino / Project Guidance / Re: Arduino Programs on: July 20, 2014, 10:28:48 am
It is an arduino with a 2.8 tft screen that I want to use for games and applications.
Which Arduino?  Because if you're talking the popular 8-bit kind with a few k of RAM, I think you might need to re-consider what kind of "games" and "applications" it can run.
10  Using Arduino / Project Guidance / Re: Arduino + Hue? on: July 20, 2014, 10:03:27 am
Maybe start with this?

https://github.com/bsalinas/ArduinoHue

I used the complicated google search term "Arduino + Hue".
11  Using Arduino / Project Guidance / Re: Arduino Programs on: July 20, 2014, 09:46:19 am
A "hex code interpreter" is the processor itself.

Is this what you want?
http://bitlash.net/
12  Using Arduino / General Electronics / Re: What capacitor will keep arduino live for 500ms? on: July 17, 2014, 09:27:48 am
Here's how I calculate hold up.  Start with an equation that determines energy in terms of voltage and capacitance.  Then solve for C.

E = (1/2 C * Vstart^2 -  1/2 C * Vdropout^2)

For the algebra challenged, here's the steps broken down to solve for C.  
1.  Take your circuit's current times the circuit's voltage, to get Power (then double it)
   P = 2x (Voltage * Current)

2.  Calculate energy required by multiplying power by time.
 E = Power x HoldUpTime

3.  Calculate the V^2
Vrange = Vstart^2 - Vdropout^2

4.  Solve for C.
C = E / Vrange


An Arduino board by itself draws 30-40mA depending on which regulator, so assume 50mA for margin.  The ATmega328 chip is only rated to 4V (or so) at 16MHz.  


1.  P = 5V * 50mA = 250mW * 2 = 500mW
This is an extreme estimate.

2. E = 500mW * 500mS = 250mJ
Time is 500mS (or recalculate for 100mS)

3.  Vrange = 5^2 - 4^2 = 9V
The 4v dropout is probably higher than it really is, so you get some additional margin.

4.  C = 250mJ / 9V = 0.02777 F
So thats 27mF or 27,778uF.

I'd probably round up to a 33,000 or 47,000uF.  However, the whole calculation has lots of margins built into it, so its your call.

No need for a Supercapacitor/EDLC.  You can get away with a regular aluminum electrolytic.  Not critical, but try to get the lowest ESR you can.  
13  Using Arduino / Programming Questions / Re: Using a short to prevent program form running on: July 17, 2014, 09:03:20 am
Specifically, you need to configure it as INPUT_PULLUP.

Not needed with the code posted, since that does a digitalWrite(pin, HIGH) which will enable the internal pull-up for input pins.
Well, no.  Since the code posted configured the pin as an OUTPUT...
14  Using Arduino / Programming Questions / Re: Using a short to prevent program form running on: July 16, 2014, 10:37:42 pm
Thanks for all of this but I am still battling to picture it all.
Code:
void setup()
{    
    pinMode(13, INPUT_PULLUP);
 
}
This line tells the Arduino to make Pin 13 an INPUT and it connects a resistor internally to 5V (VCC).  So if *nothing* is connected to the pin, it is "pulled up" to a HIGH.  If the pin is connected to GND then the pin will be "pulled down" to a LOW.

The key is the "_PULLUP".  Without that resistor, the pin's value would randomly float between a HIGH and LOW.

and then in the loop

Code:
void loop()
{
    if (digitalRead(13)==LOW) {
      //  The actual program....
    }
As I said above, when the pin is connected to GND, the pin goes LOW, so then the if-statement becomes TRUE and begins to execute.
15  Using Arduino / Programming Questions / Re: Can you set up multiple delays in your program? on: July 16, 2014, 10:34:39 pm
What do you mean "multiple delays"?

Your code would benefit, significantly, from for-loops.

http://arduino.cc/en/Tutorial/ForLoop

Code:
  alpha4.writeDigitAscii(3, '1');
  alpha4.writeDisplay();
  delay(1);
  alpha4.writeDigitAscii(3, '2');
  alpha4.writeDisplay();
  delay(1);
  alpha4.writeDigitAscii(3, '3');
  alpha4.writeDisplay();
  delay(1);
  alpha4.writeDigitAscii(3, '4');
  alpha4.writeDisplay();
  delay(1);
  alpha4.writeDigitAscii(3, '5');
  alpha4.writeDisplay();
  delay(1);
  alpha4.writeDigitAscii(3, '6');
  alpha4.writeDisplay();
  delay(1);
  alpha4.writeDigitAscii(3, '7');
  alpha4.writeDisplay();
  delay(1);
  alpha4.writeDigitAscii(3, '8');
  alpha4.writeDisplay();
  delay(1);
  alpha4.writeDigitAscii(3, '9');
  alpha4.writeDisplay();

Turns into:
Code:
  for(int i='1'; i =< '9'; i++) {
    alpha4.writeDigitAscii(3, i);
    alpha4.writeDisplay();
    delay(1);
  }

If you got really clever, you could use function calls to cut down even more.
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