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1996  Using Arduino / LEDs and Multiplexing / Re: RGB LED strip code questions (Sparkfun Pro Micro, LPD8806) on: June 27, 2013, 02:44:38 am

1) Does "tick" just continue to count up to 4,294,967,295 (because it is an unsigned long) and then stop? What is the point of this?

It doesn't stop, it goes back to zero. There's no 'point', it's just how binary numbers work.
 
2) In handlestrip(case 3) below, does every pixel in the strip turn on when "tick" is a multiple of 100, and then off when "tick"/50 has a remainder of 1 (e.g. at 51; 101; 151; 201...)? Is there a better way to adjust the rate of "strobing?"

Yes. Yes.


3) How would I implement the ledbeltkit functions found later in the code (colorwipe, colorchase, dither, larson scanner, etc.) into additional cases in handlestrip() while retaining the ability to cycle through colors?

4) Would it be possible to read the last color that was displayed on the strip/pixel and then display the opposite color? Or, would it be possible to do a strobe in predefined colors while still retaining the ability to cycle through colors? For example, when using one of the strobe functions, instead of turning one color on and off, I want it to strobe between two colors - one that comes from GetColor() and another that is predefined depending on what GetColor() returns. (So, anytime GetColor() returns red, the second strobe color will be yellow. Anytime GetColor() returns blue, the second strobe will be white.. etc.)

It's all software so anything's possible... smiley
1997  Using Arduino / LEDs and Multiplexing / Re: WS2811 not working just yet .. on: June 27, 2013, 02:34:48 am
Not really sure what TLS3001 stands for but I don't see an arrow anywhere..  smiley-confuse

If you type "TLS3001" into google you'll find it's a LED controller chip. One that doesn't respond to WS2811 signals.

Mystery solved!
1998  Using Arduino / Microcontrollers / Re: How does the Arduino Uno program? on: June 27, 2013, 02:30:14 am
The Arduino Uno has a little program running on it (the "bootloader") which talks to the Arduino IDE. When the IDE sends some code, the bootloader downloads it into the memory of the chip.
1999  Using Arduino / Microcontrollers / Re: Arduino connection to Android device through USB hub on: June 27, 2013, 02:27:20 am
I *DID* click on the link, but couldn't read your mind as to what specifically you were trying
to refer to. Simply saying "An Arduino Leonardo will do it" isn't very explanatory.

OK, my bad. You have to click the link and read the text on the page, I should have explained that more clearly.

nb. The second paragraph is important (that one that starts: "The Leonardo differs from all preceding boards ...")
2000  Using Arduino / Microcontrollers / Re: ATMEGA32A-PU in place of ATMEGA328 on: June 27, 2013, 02:12:20 am
Hello smiley
I have been working with the arduino uno board for quite some time now, and am ready to try my hand at making one now. But I have access to only the ATMEGA32A-PU 40-pin DIP here smiley-sad. Is it possible to make an Uno out of this chip?

The functionality is the same, they just have different power requirements. An 'A' chip won't work at 1.8V like a 'P' chip can (P="Picopower") but that doesn't matter much in a 5V Arduino.

You may find the Arduino IDE doesn't like burning bootloaders on the chip because it has a different device signature. You can fix that by editing avrdude.conf while you burn them.
2001  Using Arduino / General Electronics / Re: How much current flows through a MOSFET when off? on: June 27, 2013, 01:59:19 am
If you check, you'll also see the leakage for higher-power MOSFETs is much
higher, 25 uA at room temp for IRL540, for instance.

Testing on the bench of my IRLZ34N does not bear out these predictions (nor the datasheet).

With Gate connected to Source (and then to Ground) so that the MOSFET is off, I cannot measure any current flowing from Drain to Source. Certainly less than 100 nA which I think is about the limit of my equipment. This is at 5V on Drain. Even at 24V I can't spot anything.

Maybe yours is a brand new MOSFET that needs a bit of burning in. smiley

The number in the datasheet is the maximum value. Usually it will be less than that. It's also highly dependent on temperature, the datasheet will give values at different temperatures.

2002  Using Arduino / General Electronics / Re: How does usb work on: June 27, 2013, 01:46:05 am
"the USB system is probably one of the more cunning inventions for computers"

So cunning you could brush your teeth with it.

2003  Using Arduino / Microcontrollers / Re: Arduino connection to Android device through USB hub on: June 26, 2013, 03:24:30 pm
Quote
An Arduino Leonardo will do it.
Can you explain what there is about the Leonardo that is different from any
other Ardiuno?

If you gooogle "arduino leonardo" or go to the main page and click on "Leonardo" you get this:

http://arduino.cc/en/Main/ArduinoBoardLeonardo
Yeah, sorry I wasn't more specific with my question. When you said the Leonardo will do it,
won't "any" Arduino also do it, or has the Leonardo something special?


You know how I know you didn't bother clicking the link I provided...?

2004  Using Arduino / Microcontrollers / Re: Analogread on Attiny85 on: June 26, 2013, 03:23:42 pm
When I have an unconnected jumper wire to Pin2 (A1), I get some random value (~400) and the next reading ~1023. And then again ~400 and ~1023 again...

Any idea?

Sounds perfectly normal to me. Try attaching something to the wire (1.5V battery...)
2005  Using Arduino / Microcontrollers / Re: A year on 9V battery, how to convert voltage ? on: June 26, 2013, 03:22:13 pm
If you're worried about battery life then 9V batteries have one of the worst power capacities of any battery type.

2006  Using Arduino / General Electronics / Re: Hot plug adafruit sd logger shield causes windows USB disconnect chime on: June 26, 2013, 03:15:19 pm
Maybe there's a big decoupling capacitor on there that sucks a huge amount of current when it's powering up, causing a voltage drop and resetting the USB.

Possible but everything is surface mount.

They only have to work at 5V so don't let the physical size fool you, some of those surface mount caps have quite big capacitance. SD cards need a fair bit of power (over 200mA) so I'd expect them to be hefty.

Another possibility is that some data pins connect before the power pins and cause a short.

Bottom line: Plugging shields in while the Arduino is powered up isn't a good idea.
2007  Using Arduino / General Electronics / Re: PS2 Keyboard Interference on: June 26, 2013, 03:07:42 pm
If it's less than a foot long it's nothing to do with ferrite beads and you're doing something seriously wrong, eg. Not connecting one wire of the twisted pairs to ground.

PS: For wires that short you don't need CAT5 unless you're living right next to a broadcast antenna or something. CAT5 is designed to carry data signals which are orders of magnitude higher than anything an Arduino can produce. For a 16kHz keyboard signal it's completely unnecessary (and may make things worse - by giving you a chance to wire it up wrong).

2008  Using Arduino / General Electronics / Re: Hot plug adafruit sd logger shield causes windows USB disconnect chime on: June 26, 2013, 02:56:12 pm
Sounds like a power supply problem.

Maybe there's a big decoupling capacitor on there that sucks a huge amount of current when it's powering up, causing a voltage drop and resetting the USB.
2009  Using Arduino / General Electronics / Re: Pull-up for Arcade Button on: June 26, 2013, 02:54:20 pm
Hmmm, so would something like this be better?

Both will work equally well, if a pullup is required. OTOH one of them lead to easier/neater wiring and/or less soldering.

Your chip is an analog chip, which is a bit of a strange choice. It will work, but it's not ideal. Yes, it needs pullups.

Normally you'd use a digital chip like the 74HC165 (which needs pullups, too...)
2010  Using Arduino / General Electronics / Re: Pull-up for Arcade Button on: June 26, 2013, 10:08:46 am
I think what is confusing me is that there are 3 pins on the button.
Where is my "understanding" of it failed?

The failure is in thinking you have to use all of them...

There's three pins, you only need to use the ones that make sense in your application. It's OK if there's one left over.
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