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1  Using Arduino / Programming Questions / Re: DNA computing? on: October 01, 2014, 11:51:05 pm
You'll still need to provide a sample, though, with all the problems I mentioned above. And the device will have to be thoroughly cleaned between samples to avoid cross-contamination and false readings. How are you going to do that? Windscreen wipers won't be good enough.
2  Using Arduino / Programming Questions / Re: Adjusting simple (so it should be) shift register coding for a different result on: October 01, 2014, 11:35:33 pm
You are asking about the speed of the servo and I'm talking about the position of it. Two different things. The speed of the servo will be very difficult to detect. Knowing the position of it will be a lot easier and give you similar results. If you want to use the speed, then I'm unable to help you, as I don't know how to detect when a servo's speed varies. I don't know if that is even possible.

The way I see it is:
If the servo and pot are in the centre position, only the centre light will be on. Turn the pot fully to the right and all the right-hand LEDs come on and incrementally go out as the servo turns to the right. When the servo is fully to the right, only the rightmost LED will be on. Turning the pot fully to the left from this position will light all the LEDs and these will incrementally go out as the servo moves to the left, leaving only the leftmost LED on when the servo reaches the end of its travel. Any position that the servo stops between its limits will be shown (approximately, unless you have 180 LEDs  smiley ) by which LED is lit.

So you will have a position indicator, which will also show you how far the servo (if it's moving) has to travel before it reaches the set position. How does that sound to you?

There's no point in doing any coding until you've got the parameters set correctly. You don't start driving until you know where you're heading for, even if you don't know the route you need to take. Otherwise you could end up driving 100 miles when you only want to go next door.
3  Using Arduino / Programming Questions / Re: Unable to break out of "while" loop on: October 01, 2014, 10:15:38 pm
please use code tags as stated in the guidelines how to use this forum. ==> The # button above the smiley's.
That improves readability.
As does removing all those unnecessary blank lines.
4  Using Arduino / Programming Questions / Re: How to move values through an array, slowly / slow progression through a "for loop" on: October 01, 2014, 09:49:17 pm
What you need is something like this (Pseudo code):
for(int i = pixelEnd-1; i > pixelStart; i-- ) {
change your LEDs;
wait a while;
For wait a while, see the 'blink without delay' example, either in the learning pages of this site or in the IDE.
5  Using Arduino / Project Guidance / Re: Apartment Door Unlocker on: October 01, 2014, 09:26:49 pm
You need to increase your home security - not reduce it further. Once a criminal gets inside the front door he can do the rest of his stuff (such as sniff your wifi for your bank details) in perfect privacy.
Or break into a flat [apartment] where there was no reply to the bell (they're out). Maybe HIS flat [apartment]!
At the very least build a device that requires an obscure SMS from your phone - and, ideally one that changes regularly.
But I'd still check with the landlord, as it might invalidate his landlord insurance and make the OP liable for any claims.
Much simpler to carry a key.
And much safer.
6  Using Arduino / Project Guidance / Re: ProfiBus and Arduino on: October 01, 2014, 09:03:50 pm
My crystal ball has crashed, so I'm unable to see your code.
7  Using Arduino / Project Guidance / Re: Suggestions on how to approach this sound related project please? on: October 01, 2014, 08:29:13 pm
Projecting the lyrics onto the glasses might be better, but you'd have to track where the glasses were and keep the projector aimed at them. Not easy if the singer is moving around a lot.

For the singer to be able to read them, the lyrics would have to be turned through 90o horizontally. The easy way to do that would be to project into a mirror first.
8  Community / Bar Sport / Re: optical power lines? on: September 30, 2014, 12:25:15 am
cooking people is going to be a problem with any wireless energy transfer scheme that has a significant power density. 
That is what I was implying. High power, high frequency, RF or high power laser light will do that.
They could put the laser beam into a protective metal tube or two...they could raise the tubes on towers, for safety...have a grid of them to supply power throughout the country...
9  Community / Bar Sport / Re: Poll. Which are the safe frequencies? on: September 30, 2014, 12:00:38 am
Well most people don't stand under voltage lines...
Some people live, sleep, eat and work under them.  If your home happens to be under a 400KV line, you have little choice.
10  Using Arduino / General Electronics / Re: motor and L293DNE problems on: September 29, 2014, 11:48:42 pm
293, Arduino and motor power must all have the same ground.

The diagram shows none of the 4 GND pins in the middle of the 293 connected.... I guess they must be though, else your meter won't show 9V output.
Did you miss the dark blue connection on the diagram?
11  Using Arduino / Programming Questions / Re: DNA computing? on: September 29, 2014, 11:35:01 pm
But sequencing the DNA, in itself, is not a casual task for a humble door lock.
How would you get the sample?
Prick your finger and smear the blood? ...ouch!
Spit on it?...yuk!
Other bodily samples that I won't go into here? ...even more yuk!
Pull out a hair and feed it in? What happens when your visitor is bald?  smiley-mr-green
12  Using Arduino / Programming Questions / Re: Adjusting simple (so it should be) shift register coding for a different result on: September 29, 2014, 11:14:36 pm
Goal: I would like the  LEDs to light all the way (1-8) with the speed of the servo and reverse as the servo slows down and reverses.
Firstly, I would use an odd number of LEDs so that the centre one is lit even when the servo is stationary. In fact, it would always be lit. Instead of looking at the speed of the servo, it would be easier to determine how far away from it's target position it is. You know the position it's in (= the current position). Lets call it curPos. And you know the position you want it to go to (= target position). Lets call it tarPos. If curPos < tarPos the servo will be going forwards and if curPos > tarPos the servo will be going backwards.  tarPos - curPos will give you the distance to be moved forwards and curPos - tarPos will give you the distance to be moved backwards, so you can calculate the number of LEDs to be lit. You'll need to update curPos as the servo moves nearer to the target position. When curPos == tarPos all the LEDs, except the centre one, will be off. You could use a tricolour LED for the centre one and have it showing white when the servo is stationary and red when it's moving.
If you agree that that is the way you want it to go, we can start thinking about the programming.
13  Using Arduino / Project Guidance / Re: spdif (toslink) switch on: September 29, 2014, 10:01:03 pm
basically like this (sorry for late reply)

i been reading about mux looks like it will do what i need but cant find a digital one with enough inputs
Most analog MUXs will handle a digital signal, as it's exactly the same as a 0 - 5V square wave analog signal. The maximum frequency and peak-to-peak voltage is what you need to look out for.
14  Using Arduino / Project Guidance / Re: Apartment Door Unlocker on: September 29, 2014, 09:28:50 pm
You're negating the security of the system. It'll let anyone into the building who presses your button, even a murderer!
Does your landlord approve of this?
Does his insurance provider approve of this?
Does the local Police's Crime Prevention Officer approve of this?
15  Community / Bar Sport / Re: Every Circuit.... on: September 28, 2014, 10:09:10 pm
Closed it and reopened it. It started immediately!
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