Been playing with this for a few days and I'm finally here for help.

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Been playing with this for a few days and I’m finally here for help.

I have a regular 5050 RGB strip, NUM_LEDS = 1, running on a P9813 driver from a Wemos board, ESP8266. I’m reasonably sure the issue is 8266 related and I hope there is a way to solve it.

The issue is that as you reduce the brightness once it gets too low the LED’s start to pulse/flash which only gets worse as you dim even further. For an RGB 255,255,255 the flashing starts at fadeLightBy(205). A similar result happens if you only use one channel at full brightness but reduce that from say 255 blue down to zero, at a certain point at the low end the flashing starts. The power supply all looks good, 8266 running from a phone wall charger, 5v to the P9813 from the 8266 as well as 12v from the wall for the strip (into the P9813)

I’ve read all sorts about this being a software PWM implementation issue, and that the 8266 does have some hardware PWM pins but FastLED doesn’t support them?

If this is an 8266 issue I guess I have 2 questions, will FastLED be updated to support it anytime soon, and if not what board should I look at, I need to have WiFi functionality too.

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If I understand you correctly, you’re using two separate power supplies? Just want to check that you have a common ground wire between those?

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I do not have a common ground, and I thought this might come up. I’ve attached an image of the P9813 board I am using. The Wemos is hooked up to the 4 pins at the top, (wemos powered over a USB cable), RGB strip on the right and on the left is the 12v in from a mains adaptor via a 5.5mm DC jack. Can I just bridge the the 2 GND pins on this board?
missing/deleted image from Google+

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Double check continuity with a multi-meter that the 12V GND and the GND pin on those top four pins are connected. (You might even just be able to look at the back of the PCB to see this. I would expect them to be common.) If you have a wire connected to that top GND pin back to GND on the wemos then everything should have a common ground and you’re fine there. I don’t have experience with the 8266 so it’s quite possible the issue is somewhere there. If you have an UNO or another Arduino board you might hook that up to at least confirm that the P9813 board and LEDs are all working correctly.