btf strip fcob 12v 720 leds/m chip on ledstrip is ws2811 F on chip
works in segments of 5cm that you can control .
i am strugling with setup for these ledstrips.
hardware
controller mini esp8266 flashed with wled
levelshifter 3.3 to 5v
gpio 2
gnd 5v and 12v are the same
tests
I made 2 teststrip of 5 segments. Both respond badly.
Trying Solid first segment is always different from the other four segments.
eg solid red
seg 0 is blue and the rest red
if solid green
seg0 is blue and the rest is green
solid blue
seg 0 is liightblue and rest is blue
tried with both strips both the same.
My thought a setting in wled but cannot get it right.
sorry for late reply. mini esp8266 levelshifter 4chan. 1 channel used gpio 2.
fcob is 12v. data 5v gnd is common with gnd 12v.
i have seversal ledstrip worked like a charm with the others in this configuration. just with fcob lightstrip 12v response to data is erronous. blinking even with solid conf. checked chip on led strip is ws 2811 F. tried several strips fcob 5segments long. same bad result.
thx for tip i will try to put scope on data channel. must be baddata = prog fcob special or hardware levelshifter bad or bad connection.
thx for responses. levelshifter i used was bad. tried now with ic buffer not inverted CD4050BE and now it works also with fcob.
That is the levelshifter i used(see picture) when not working with fcob led strip. wled needs high data exchange apparently.
I noticed also lately this levelshifter performs badly with spi cannot handle speed. The advantage of this levelshifter it works well with i2c and is bidirectional.
For wled you only send data dont need bidirectional levelshifter.
The buffer i used cd4050be . power 5v and gpio 2=> 3.3v signal to one of buffer inputs. then corresponding output of the buffer to the ledstrip as output.
As far as levelshifters, the I2C type has been well recognized as too slow for LED data.
The recommended devices are based on 74AHCTxxx or 74HCTxxx chips to match speed with proper input and output voltage tolerances (3.3V → 5V).
Many gates can be used reliably: 74AHCT32, 74AHCT125, 74AHCT244, 74AHCT245, to name a few.
The cd4050be devices you used are unfortunately marginal at best as levelshifters for addressable LED data. Their guaranteed input voltage specifications don’t meet the tolerances that may be present with ESP GPIOs. Additionally, they have fairly poor response times with a 5V supply.
Once again, I’m not disputing that you’ve had some success with the 4050 device.
Any given chip may respond better than the mfg. specs and work for your setup.
In the long run, you’ll be better off choosing a chip that has specs that are guaranteed to work.
Certainly, that’s the best recommendation for anyone trying to connect WLED to various LED strips.
Thx for info. I had the cd4050be available. And tested it it worked
. Put scope on it had my 5v data pulses. specs are as you said for speed not so good. I ordered the correct buffers as you mentioned. Now i have good setup hardware driving ledstrips with wled.
