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4651  Using Arduino / Installation & Troubleshooting / Re: Arduino Pro Mini 3V3 Voltage pins on: September 26, 2011, 07:42:58 pm
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Once the usb is connected shouldn't be 3.3V on all pins?
Not if you are using the 3.3V version of the Mini Pro...

Which,
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There is 3.2V on VCC
Implies you are using the 3.3V version.

The Pins will not be any higher than VCC.
4652  Using Arduino / General Electronics / Re: Anyone recognize this sound board? on: September 26, 2011, 08:40:51 am
It is impossible to read anything on the chips in that image.
4653  Using Arduino / Programming Questions / Re: Serial Monitor weirdness with lengthy switch statement on: September 25, 2011, 09:49:01 pm
I don't understand what you are saying/asking.

If the arrays don't change, put them in PROGMEM instead of RAM.  Probably easier than passing back and forth over serial.
4654  Using Arduino / Programming Questions / Re: Serial Monitor weirdness with lengthy switch statement on: September 24, 2011, 04:08:51 pm
Any time you add code that has strings (and Serial.print()) that starts to point to RAM exhaustion. 

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I'm using a duemilanove ATmega 168
The ATmega168 has 1k of SRAM.

You have declared 23 integer arrays with 68 elements each.  68*23 = 1564 bytes....  You've run out of RAM before the sketch even starts.  Also, each string used in a serial.print() consumes RAM as well.

You probably need to look at using PROGMEM.
4655  Using Arduino / Programming Questions / Re: Learning new languages (avrc and asm) on: September 24, 2011, 03:38:09 pm
The "Arduino Language" is C.   Stuff like digitalWrite() are just C-functions.  You could easily look at the underlying source code and see the "avrc" that was used to create those functions.
4656  Using Arduino / Project Guidance / Re: Can an Arduino power an XBee and an LCD? on: September 24, 2011, 10:09:13 am
You need to understand the difference between Power, Voltage, and Current.  (You are only focused on Voltage.)

Power is the product of Voltage and Current.  Voltage is pressure.  Current is flow.  

Since current is flow, you need to determine how much current each device is going to consume and how much current your source can provide.  Look at the spec sheets for each of the components you are using to determine how much current they are going to consume (or draw.)

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I used a 9V external battery to run tests with my arduino
9V batteries are an ABSOLUTELY LOUSEY source of current.  You are FAR better off using a AAs than a 9V.
4657  Using Arduino / General Electronics / Re: Using a 5 volt regulator on: September 24, 2011, 09:24:47 am
You will need a heat sink for the regulator.

It never hurts to add the recommended capacitors to the input (and output) of a regulator.

You have linked to a 1uF cap.  So unless you are going to put those three in series, it isn't 0.33uF.  You can easily for 0.33uF (ceramic) caps on eBay.

You have stated in your post (or your profile) where you are in the world.  They may be better options for fewer parts than eBay.
4658  Using Arduino / Installation & Troubleshooting / Re: Arduino Pro Mini 3V3 Voltage pins on: September 23, 2011, 06:59:46 pm
Only Pin 9?

Is there anything else connected to the pin?

What is your 3V3 (or VCC) pin measuring?
4659  Using Arduino / Installation & Troubleshooting / Re: drivers on: September 23, 2011, 06:58:22 pm
Why did you create a poll?

What happens when you try to "load' them?  What steps are you taking?  What errors or you seeing?  Saying "it doesn't work" won't help to get an answer.
4660  Using Arduino / General Electronics / Re: Arduino pro mini giving different readings on battery power vs usb power on: September 18, 2011, 06:22:21 pm
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don't understand why it causes it to not work when it's supplying the same amount of power as the usb cable, but maybe 1 amp isn't enough...

Keep in mind that Voltage, Current, and Power are all very specific terms.  They are very different (related) things, but you are interchanging their usage.   Voltage is "Pressure", Current is "Flow", and Power is a function of both.  Power = Voltage times Current

Current is "sourced" and "drawn."  So a source rated for 1Amp means it is capable of suppling 1Amp.  A 7805 (and similar linear regulator) can source 5V @ 1A if they are properly heat sinked.  (Which would be 5V * 1A = 5Watts of Power.)  Other wise their output capacity could be as low as 100mA.

So your comment "they provide the same power" isn't correct.  USB and the Regulator both provide 5Volts.  However, their Power capability is different since USB only sources 500mA and the regulator can (under the right conditions) source 1A.

It sounds like you were connecting your 5V regulated output to VIN and not the 5V node.  So the on board regulator was trying to regulate 5V-in to 5V-out, which doesn't work.
4661  Using Arduino / Installation & Troubleshooting / Re: Brief digital high on start up on: September 18, 2011, 12:57:58 pm
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Tried forcing outputs low, but still get it.

With hardware or software? 

During RESET all I/O pins default to INPUT which is high impedance.  It is not uncommon for a floating pin to briefly appear high.  Does the same behavior happen when you use an external pull-down (or pull-up) resistor?
4662  Using Arduino / Installation & Troubleshooting / Re: USB port not working anymore on: September 18, 2011, 12:48:39 pm
Can you please draw a diagram of how you had your hardware connected?  Your ultra + condensed + single + line description isn't descriptive enough.
4663  Using Arduino / Installation & Troubleshooting / Re: Upload problem - Mac - Arduino UNO on: September 18, 2011, 12:46:46 pm
Are you using an USB Hub?  If so, connect directly to the Mac's USB port.  (Try moving to different ports since some of the external ports are connected through an internal Hub.)
4664  Using Arduino / Programming Questions / Re: Showing arduino status on a web page on: September 18, 2011, 07:52:18 am
This would be pretty simple with a little PHP.  The arudino loads a page (which is a PHP script) that logs what time the hit occurred.  Your visitor viewable web page also loads a PHP-based script that checks what the last Arduino hit was and decides to print "online" or "offline."
4665  Using Arduino / Project Guidance / Re: led doesn't turn off! on: September 10, 2011, 06:45:00 pm
How long do you think it will take from when the digitalWrite LOW until the next digitalWrite HIGH occurs?  It is very likely the led is being turned off and then back on fast enough that your eye can't see it.

Put an additional delay(1000) after turning the led off, to see if the overall behavior changes.
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