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Don't work on my Arduino MEGA 2560

Open Ldoppea opened this issue 7 years ago • 5 comments

Hi,

Hi just tried your SimpleNeopixelDemo 'as is' with my Arduino MEGA 2560 and I did not succeed to make it work.

Your code is using PORTB, bit 4, which seems to be the pin 10 on the MEGA. Do you confirm?

When I run the code with rainbow mode, only the first led is lighted and it is strangely blinking. If I remove the wire jump from pin10, all leds finally get a color. If I plug the wirejump back, nothing change except the first led blinking. If I remove it, all leds get a new color. The color seems to be consistent with the rainbow cycle.

If I use the official adafruit library everything works correctly.

Any idea of what I'm doing wrong?

I'm on windows 10 with Arduino 1.8.5

Ldoppea avatar Jan 15 '18 00:01 Ldoppea

That sounds like the LEDs are not seeing a delay to give them a chance to latch the new color values.

Maybe your LEDs need a longer delay? Can you try changing the value of RES here...

https://github.com/bigjosh/SimpleNeoPixelDemo/blob/master/SimpleNeopixelDemo/SimpleNeopixelDemo.ino#L38

...from 6000 to maybe 50000 and see if that helps. Report back with your findings!

bigjosh avatar Jan 15 '18 15:01 bigjosh

Hi, Thx for your answer

Yes, it was my first thought and I tried 50000 and even 100000 but nothing change. Also tried 500000 but then all leds are tilting white very fast 😆

Ldoppea avatar Jan 15 '18 19:01 Ldoppea

Okay, I tried, 50000, 10000, 500000, but I did not try 10000000 which seems to work 🤣

Thx for your help.

But now the question is why such a big number?

Ldoppea avatar Jan 15 '18 21:01 Ldoppea

Not that big of a big number. 10,000,000ns = 10ms. Either (1) you've got some really slow to reset pixels, or (2) something else is going on. Easiest way to see if something else is going on is with an oscilloscope. Got one?

bigjosh avatar Jan 16 '18 03:01 bigjosh

No I don't, but maybe i'll be able to use one in the next days or weeks. If it is the case i'll try to check this.

Ldoppea avatar Jan 16 '18 18:01 Ldoppea