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[Reply #75 on:]

I see I'm not alone on this quest. I've only just begun. to read ......  
my post : http://arduino.cc/forum/index.php/topic,104672.0.html still open.
Hello all!
Cheers, lol

[Reply #76 on:]

I can't see the decoupling capacitors. Can you circle them or something?

Also, in this "non working" configuration, can you please measure what voltage you get on the +5V rail?

[Reply #77 on:]

I'm not sure why I need it though. When used for what's it's designed for, all 88 LEd's are never on all at once.. Maybe 15 at the most.

You're just hoping though, aren't you? When I boot up my collection of 32 LEDs, initially a random number of about 1/3 to 1/2 light up, before the sketch gets control and tells them to turn off.

So if you don't have designed in to handle all 88 on at once, that initial current surge might overload the power supply on the processor, shutting it down, before it gets a chance to tell those 44 or so LEDs to turn off.

[Reply #78 on:]

David, im gonna give you my 5 cents( dont have smaller change at the moment)- first, if you are questioning people who have a much more stable knowledge of things( like nick, Grumpy mike etc) at least hope you have a reason to do so. Which from the posts you dont seem to have to start with.
2nd- that breadboarded circuit is quite prone to have a problem somewhere( i should know by all my past experiences lol), so problem might come from there.Youd nedd to start by being patient and check all continuity  (which is deffo a endless task i know)
3rd NICK is quite right when he asks...WHERE ARE THE DECOUPLING CAPS ?!?!? Cause, for the goodness of me, i cant bloody see them...

[Reply #79 on:]

Also, in this "non working" configuration, can you please measure what voltage you get on the +5V rail?

No problem. I like this. Now we're starting to troubleshoot it.

[Reply #80 on:]

The soldered LEDS...Have u checked the continuity of it all, so you're sure there's no crossed soldering, cold solders, etc? Checking that continuity is intact, to start with( despite being a humongous task) seems a good start. Then the breadboard...Only then you should worry about the rest.
With continuity i mean checking each junction individually( i know, slow task and "boring" ).
But you have to start somewhere, and follow a rational logic. Otherwise you will  get nowhere !! Nick been quite patient with you, for which you should be thankful. But unless you are prepared to follow his instructions,  not much point there. Cause look at the amount of pages we been through over such a simple task !!
as an option you can think prototyping the circuit as will be easy to check continuity, soldering etc, and then will have to work, unless you make a mistake again. But there will be much easier as there's no ratsnest pile of wires to go wrong.
Also- That amount of leds is a bit ridiculous to be honest unless you follow another tested circuit prepared to power all those leds.
So you do need to rethink your strategy !! Cause this path wont get you anywhere.
Good luck with it !!

[Reply #81 on:]

You're misunderstanding the situation again iyahdub. You're making suggestions to problems that don't exist and making false claims that I'm not doing things I should be doing or vice-verse.

The soldered LEDS...Have u checked the continuity of it all

Of course that isn't a problem because they all light up. Come on man; really?

But unless you are prepared to follow his instructions

I have been.. Obviously. There's an example of you making a false claim again.

Cause look at the amount of pages we been through over such a simple task !!

That's because there is a strange problem somewhere and the correct way to wire it doesn't work. Could be a breadboard issue.. Who knows. That's the reason it's taking a while to figure out. I've already got it working correctly but it is using bizarre wiring. We're trying to figure out WHY. Come on man. Quit misunderstanding what's going on.

That amount of leds is a bit ridiculous to be honest unless you follow another tested circuit prepared to power all those leds.

Here again is another example of you missing a critical detail that has already been posted. I mentioned already that I only have ~15 of them on at the most at any given time. Do you understand? That means amperage is not an issue. 13.6mA x 15 = 204mA. That is what is being drawn at most. Come on man, quit making false claims.

Cause this path wont get you anywhere.

What path? You're obviously not paying very close attention to what's going on. We're trying to figure out why the correct wiring won't work and why the "working configuration" that I've been using does work.

[Reply #82 on:]

You're misunderstanding the situation again iyahdub. You're making suggestions to problems that don't exist and making false claims that I'm not doing things I should be doing or vice-verse.

The soldered LEDS...Have u checked the continuity of it all

Of course that isn't a problem because they all light up. Come on man; really?

But unless you are prepared to follow his instructions

I have been.. Obviously. There's an example of you making a false claim again.

Cause look at the amount of pages we been through over such a simple task !!

That's because there is a strange problem somewhere and the correct way to wire it doesn't work. Could be a breadboard issue.. Who knows. That's the reason it's taking a while to figure out. I've already got it working correctly but it is using bizarre wiring. We're trying to figure out WHY. Come on man. Quit misunderstanding what's going on.

That amount of leds is a bit ridiculous to be honest unless you follow another tested circuit prepared to power all those leds.

Here again is another example of you missing a critical detail that has already been posted. I mentioned already that I only have ~15 of them on at the most at any given time. Do you understand? That means amperage is not an issue. 13.6mA x 15 = 204mA. That is what is being drawn at most. Come on man, quit making false claims.

Cause this path wont get you anywhere.

What path? You're obviously not paying very close attention to what's going on. We're trying to figure out why the correct wiring won't work and why the "working configuration" that I've been using does work.

Oh is it ?!? OK then, explain me how it worked for NICK and didnt for you ?!? Cause you have a mistake somewhere.
Projects with much less LEDS use Transistors for the sake of proper functioning, and you wanna light a whole neighbourhood with a AA battery...
And still you keep saying that  the way you been explained is the wrong way ( but only for you of course cause everyone else sees it is correct).
And NO,m we already figured that it isnt enough powering... NICk done the numbers assuming it will always draw 14 mA, which it wont, as average is 20mA  and that would be a expected value( which we know fluctuates). NIck done the number for us, but he also said to you that that was just for the leds, and not the chips, or have you only read what suited you !? So unless you are prepared to rethink your strategy, this aint going anywhere.
Anyway, im not here to argue, or enter into kids type of debates( oh u said i said, you wrong im not).
As i said, i wish you good luck.
Im offski !!

But my advice would be RETHINK YOUR STRATEGY !!
It is your inability to SEE the obvious that doesnt allow us to get anywhere here.
Projects with much less LEDS use Transistors for the sake of proper functioning, and you wanna light a whole neighbourhood with a AA battery...

[Reply #83 on:]

OK then, explain me how it worked for NICK and didnt for you ?!? Cause you have a mistake somewhere.

There you go misunderstanding things again. We already know there is something wrong somewhere. Could be anything. It does work though when wired slightly differently than the correct way. The question is WHY.

Projects with much less LEDS use Transistors for the sake of proper functioning

He said we don't need them. That ends that.

I tried a 2 amp power supply this morning and it didn't fix the problem. Of course it didn't fix the problem because whatever the problem is, it obviously, obviously, obviously, obviously, isn't amperage. For reasons stated in previous posts. Obviously.

The bottom line is you are constantly misunderstanding what is going on and making uninformed assumptions. Stop it. I've proven you wrong on every one of your uninformed assumptions. The correct way forward on this is to continue where Nick left off. We're getting 5v to the rails (of course) so the next step is to run whatever test comes next. Remember, the thing does work. Just not when wired correctly. Why?

[Reply #84 on:]

So there is a mistake from your side ... Not working correctly means its not working.
And the only thing you have proven so far is that you havent been able to get it to work.
Easy to see you have no idea of what electronics are cause for you, lighting some leds, is working...NO ITS NOT. And most probable is lack of current.
So, you may want to rewrite your statements !
I give up

[Reply #85 on:]

You're misunderstanding what you're reading again. As usual.

Not working correctly means its not working.

For the thousandth time, it does work, but not with the recommended wiring.

the only thing you have proven so far is that you havent been able to get it to work.

For the thousandth time, it does work, but not with the recommended wiring.

I am completely convinced that you are not qualified to help with this. Not because you don't have the knowledge, but because you are wildly, incredibly horrible when it comes to reading comprehension. You misunderstand EVERYTHING.

Again, for the second time, the next step is to run whatever the next test is. We've verified 5v coming to the rails. What's the next test.

[Reply #86 on:]

Those caps just appeared then, eh?

The thing is, you may have more than one problem. So if the caps don't fix it, don't just pull them out.

Can you do this?

• 4.8V looks OK (I usually get 5V) so can you compare with and without the circuit connected? (ie. what does your Arduino normally put out?)
• Work your way along and check the Vcc of each chip. If one missed out then that could be the problem.
• I don't suppose you have a logic analyzer there? That would be my next step.
• Is it possible that the "non working" configuration (when you have the power connected) is actually that the sketch is not displaying anything? I mean, is "not working" really "working" but with a bug in the sketch?
• If you are convinced that some of the LEDs are displaying what they are commanded to display, it should be simple to isolate it down. After all you have 11 chips basically wired the same. Just by removing the data wire (the Q7' to DS) you should be able to test each individual chip. Do that and see if one (or more) chips behave differently to the rest.
  

[Reply #87 on:]

Test Results:
Test:
1. 4.94 coming from the arduino, 4.94 connected to circuit w/no LED's on.
2. done. I also know one didn't miss out because I can get them all to light up on command (not with this wiring).
3. don't have one
4. That doesn't seem likely. I haven't changed your original sketch except the numberOfChips variable. Besides, it works almost perfectly if I disconnect 5v line and add only one cap and one led from Vcc of first chip to ground.
5. When wired as described above, any LED will light up when told to and turn off when told to. The entire thing will light up if I tell it to. The only glitch is, that some of the LEds toward the end (chip10 & 11) will twitch/flicker sometimes. I believe this is from noise but I can't solve it because adding more than one cap makes it worse.It also matters where I put the cap. It has to be at the beginning of the chip row. If i put it at the middle or end, it behaves worse. There is also one LED that stays on most of the time when different LEDs are being told to turn on and off. It's on most of the time but sometimes turns off. If I send the 'all off' command it will turn off. I believe this is also dues to noise.

[Reply #88 on:]

OK, let's try something. I'm convinced we have to get it to work "powered correctly", so the question is, why don't the LEDs light up if you run that 5V wire?

With that wire in place, just upload a totally different sketch, like File -> Examples -> Communication -> ASCII table. Open the serial monitor and see if the ASCII table appears. This will confirm whether, or not, connecting the power is somehow making the processor reset (or just fail).

[Reply #89 on:]

Yup. ASCII table worked. A few random LEDs lit up too. Likely due to noise. What's next?