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I was playing around with an Adafruit Flora and a strip of NeoPixel LEDs. After uploading the sketch to the Flora (via Arduino IDE), the LED strip lights for about 1 second and then dims to a dull orange color for all the lights. When this orange color appears, it seems to indicate that the Flora has crashed. If I unplug the Flora from power and plug it back in, the LEDs light again for about 1 second and then it crashes again.

The time between boot and crash is short enough that I can't upload a new sketch.

So how would I go about rescuing the Flora? Is there a couple pins I can jumper to put it into bootloader mode? Or some other way of resetting the Flora so as to remove the offending code?

  • Sounds like it might be a power problem, perhaps your LEDs are overloading your USB port (how many do you have?). You might try disconnecting the LED strip to verify you can still program the flora. – Chris Stratton Oct 3 '16 at 22:37
  • @ChrisStratton: 42 pixels in the strand all set to bright white. If I read the datasheet correctly each pixels draws a max of 0.2A - so that should be 8.4 amps!? Sounds awfully high? – Sam Axe Oct 3 '16 at 22:49
  • No, they should only take about 60mA each. But at 2.5A that's still too high for the on-board regulator. – Ignacio Vazquez-Abrams Oct 3 '16 at 23:04
  • And several times too much for a USB port, too. Disconnect power to the pixels and you'll find your flora is probably fine. But you'll need to rig up a suitable power supply if you want to turn more than a few of them on dimly. – Chris Stratton Oct 3 '16 at 23:07
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42 pixels in the strand all set to bright white.

This exceeds the power supply capability of either a USB port or the Arduino's regulator.

Likely the circuit starts out working, then once the LEDs are all on drawing high power either a protective device such as a polyfuse / PTC fuse activates trips or the supply simply sags under load. At this point the circuit either shuts down or starts misoperating, the ATmega may go into brownout protection mode, etc.

Disconnect power to your LEDs and you will probably find that the Flora is fine.

You will need to use a suitable higher current power supply if you want to light more than a few pixels of this type at any given time.

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