Hi everybody,
I’m trying to control a strip of ws2812B LEDs by MicroPython on a ESP8266 board. I followed the basic examples in this and other sites tutorials but the results I get are not consistent. I enclose a couple pictures and a short video to explain what I mean.
I initialize this way:

from machine import Pin
from neopixel import NeoPixel
from time import sleep
np = NeoPixel(Pin(4, Pin.OUT), 72, bpp=4)

bpp=4 is due to my strip having white LEDs, too.
In “BW2180B_test_1.jpg” you can see the result of this code from this site’s tutorial:

def set_color(r, g, b, w):
for i in range(72):
np[i] = (r, g, b, w)
np.write()
set_color(0, 102, 230, 128)

It’s supposed to turn all LEDs on with the color passed as RGBW argument (I inserted a 4th argument because of the white LEDs). The result is that all the LEDs are turned on with different colors in a repeating pattern: blue, yellow, white, red. If I omit the “white” component I get a repeating pattern of blue, red, green (not 4 colours as in the previous example).
More strange is a second example:

np[0] = (0, 0, 0, 128)
np[1] = (0, 0, 128, 0)
np[2] = (128, 0, 0, 0)
np[3] = (0, 128, 0, 0)
np[4] = (0, 0, 128, 0)
np[5] = (128, 0, 0, 0)
np[6] = (0, 128, 0, 0)
np[7] = (0, 0, 128, 0)
np.write()

I had to shift the argument “green” to get all green LEDs but every way I pass the arguments I can’t get all the right LEDs on: I get the first 4 green on, 1 off, 2 green on, 1 off and 1 green on as you can see in the photo named “BW2180B_test_2.jpg”. Trying to pass all the same arguments for green (0, 0, 0, 128) to contiguous different LEDs I get the pattern green, red, blue, off.
The only test giving me the expected result was the flashing of 1 green LED:

def fade_in_out(led, times, red = 0, green = 0, blue = 0, white = 0):
count = 0
while count < times:
for i in range(white):
np[led] = (red, green, blue, i)
np.write()
for i in range(white, 5, -1):
np[led] = (red, green, blue, i)
np.write()
sleep(.05)
count += 1 
all_off()
fade_in_out(0, 10, white = 128)

But if I try this passing LED 1 I get it flashing red , with LED 2 I get it flashing blue, with LED 3 I get the 5th LED flashing green in a pattern similar to the previous ones.

I tried 3 different strips (only difference the LEDs density) and got the same result.
Obviously there something i miss! Please, any hint?
Thanks in advance.