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[Reply #90 on:]

Nick, was talking with someone and he was saying something that is right- The LOL shield( Lots of leds) is already pushing it to the extreme, so 88 leds and 11 595's has to be way beyond.
I personally want to see the result of this out of curiosity, but unless he changes the circuit i doubt this will take him anywhere.
But thats me !!
Plus the faqct as soon as he disconnects the USB powering more problems will come straight away  as it will probably quadruple the noise!!

[Reply #91 on:]

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

... however earlier ...

2) same as scenarios 1 but chip 1 is separated from the others = unresponsive

I think I am misunderstanding you a bit here. I got the impression before that with the power connected nothing lit up, but you are saying some LEDs light up.

I think you need to define your terms a bit better "random LEDs" and "unresponsive" are pretty vague.

Your idea of random, and unresponsive, may be different to mine.

Perhaps a video showing the various things you are reporting? Like the "almost working", what it does when you connect the power, what happens when you type commands, etc.

[Reply #92 on:]

Sure.
"unresponsive" is defined as a scenario where commands are sent and absolutely nothing happens.
"random LEDs lighting up" is defined as a scenario where random LEDs light up and stay on, unprompted. Not always the same ones. Due to noise.

You are implying that the two different comments that you quoted contradict each other. They aren't related. With the ASCII program, a few random LEDs light up due to noise. I guess becuase that 10k resistor isn't there holding the latch pin down.. but that's irrelevant. With the main program, the whole thing is unresponsive to commands (only when wired correctly).

[Reply #93 on:]

What's the next thing to test?

[Reply #94 on:]

I'm sorry but I don't know if I can help any more. You seem to be basically in a guessing/speculating sort of mindset where any ideas I, or others, make are dismissed without any proof.

They aren't related. With the ASCII program, a few random LEDs light up due to noise.

Your proof that noise is the reason?

I guess becuase that 10k resistor isn't there holding the latch pin down..

So just guessing here.

... but that's irrelevant.

In your opinion.

... a scenario where random LEDs light up and stay on, unprompted. Not always the same ones. Due to noise.

You are just asserting "due to noise" when it could be due to low voltage. Where is the proof it is due to noise?

With the main program, the whole thing is unresponsive to commands (only when wired correctly).

There is a subtle implication here that being "wired correctly" is the cause of your problems. Not so subtle here:

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

I would have put back the "chaser" sketch (somewhere in the last 7 pages) and just leave that running and observe and probe until I worked out what was happening.


I suggested you make a video. Not done.

I suggested you try each chip individually. No response.

For the thousandth time, it does work ...

Right, so it works. We can close the thread.

[Reply #95 on:]

I would have put back the "chaser" sketch (somewhere in the last 7 pages) and just leave that running and observe and probe until I worked out what was happening.

THere we go. Another test to run. Using that sketch is a great idea because it provides instant results as opposed to having to type commands. The only thing changed in the sketch was the numberOfChips variable (from 4 to 11). Here are the results of testing with that sketch:
"my wiring" is defined as one cap near first chip, LED (going from Vcc of 1st chip to ground), and 5v line from arduino removed.
1. correct wiring = no activity.
2. my wiring = pulsing back and forth (like your video) just on the last 4 chips. (code issue I suspect).
3. my wiring with LED removed = no activity.
4. my wiring with cap removed = chips 1-3 inconsistent strobing with last LED of 3rd chip solid, chips 4-11 lit solid.
5. my wiring with cap and LED removed = same as #4

In scenario 2, 4 or 5, if I add 5v line, all the LEDs turn off. Does that give you any clues?

[Reply #96 on:]

This should help. I've done some more experimenting. That LEd w/resistor that I said needed to be there connecting Vcc of chip1 to ground really just has to be a resistor plugged in anywhere on the +- rails just like a cap. If that's not there, the whole thing doesn't work. So the working wiring is to remove the 5v line from the arduino, and place one cap and one resistor on the +- rails.

[Reply #97 on:]

Just made another discovery. The few LED's that were turning on and preventing "my wiring" from working 100% were, in fact, caused by a bug in the windows software I was using to interpret data and rapidly send commands to it. All is fixed now. To summarize, the wiring that is supposed to work doesn't work at all (I wish I knew why). Instead, the same diagram, but without all but one cap, without 5v line from arduino and with a 220ohm resistor on the +- rail, works perfectly. I'd love to know WHY, but I guess I'll never know unless someone comes up with a test to perform to find out or, is smart enough to know with the info provided.

[Reply #98 on:]

So it was working all along?

Well I'm glad it's all going now.

[Reply #99 on:]

..."the same diagram, but without all but one cap, without 5v line from arduino and with a 220ohm resistor on the +- rail, works perfectly. "

The mystery remains...First time i hear someone saying he is lighting 88 leds and 11 SR without the 5 V power ... No wonder arduino is such a success!!!

You will end up having problems as soon as you connect a external power source, i guess... I hope not, but that is almost assured

[Reply #100 on:]

So it was working all along?

Well I'm glad it's all going now.

It's working perfectly, but with the wrong wiring. The correct wiring makes it unresponsive. That's what I've been asking over and over is why.

[Reply #101 on:]

Don't know.

I remember getting up to about page 5 of another thread where the guy eventually said "oops I left out a link" ... that was after the previous 4 pages of assuring me it was wired perfectly.

Now I'm not saying you did that, but it's hard to tell remotely exactly what you have.

[Reply #102 on:]

This configuration doesn't bring anything to mind? I have to put a resistor from + to -. Is there a common scenario that causes you to need to do that? What scenario would make adding more caps cause more noise instead of less? What scenarios would make adding 5v to a circuit make that circuit unresponsive?

[Reply #103 on:]

This configuration doesn't bring anything to mind? I have to put a resistor from + to -. Is there a common scenario that causes you to need to do that? What scenario would make adding more caps cause more noise instead of less? What scenarios would make adding 5v to a circuit make that circuit unresponsive?

The kind of scenario where people wired it wrong, maybe ?!

[Reply #104 on:]

You're misunderstanding everything again iyahdub. You forgot the part about how it works perfectly. Maybe reading things twice will help you.