![]() ![]() Unless you’re doing something insanely complicated and insanely fast, you shouldn’t notice any visible difference to the display. The answer in this case is fairly simple …just put a couple of calls to yield() into the code in strategic places (one in the top of the loop function and another following the call to showStrip() , in whichever example code is being used, worked well for me). The second issue is the common watchdog-timeout issue which plagues applications which spend too much time in tight, time-critical loops without allowing the ESP8266 time to attend to its WiFi housekeeping. Almost any common, small-signal PNP transistor (2N3906, BC560) will work in this configuration specific type is not too critical. Thus this simple circuit not only protects your ESP from damage, but also provides the correct voltage swing for the WS2812 data bus, too. ![]() Unlike the more traditional common-emitter transistor circuit, the emitter follower doesn’t amplify the input signal at all in this circuit it is acting as a switch, but while the output from the GPIO is switching between 0v and 3v3, the output of the emitter-follower is switching between 0v and 5v. ![]() An emitter-follower is a non-inverting buffer, which provides a medium to high impedance on it’s input (so it doesn’t place any significant load on the GPIO pin) and presents a low impedance output (meaning it can drive more current than the ESP GPIO pin can alone). It’s very easy to isolate your ESP8266 from the WS2812 5v supply voltage and provide a low impedance drive for the WS2812 bus at the same time, using a cheap, PNP transistor in emitter-follower configuration. The first is something you need to pay a little bit of attention to, in order to prevent damage to the ESP GPIO pin. The ESP8266 wireless housekeeping requirements.When used with the ESP8266 though, there are a couple of pitfalls which you need to be aware of:. Although the article is a couple of years old and is aimed at Arduino hardware using the FastLED or NeoPixel libraries, the routines are, for the most part, directly transferable to the ESP8266 (both libraries are available for the ESP when using the Arduino framework). There’s a really captivating article on Tweaking4All illustrating the various effects (firelight, bouncing-balls, chasers, etc) that can be easily reproduced with the common WS2812, addressable, RGB, LED strips, available from just about every vendor out of the Middle Kingdom. ![]()
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