Adafruit Feather M4 Express, Руководство пользователя

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CircuitPython NeoPixel
NeoPixels are a revolutionary and ultra-popular way to add lights and color to your project. These stranded RGB lights
have the controller inside the LED, so you just push the RGB data and the LEDs do all the work for you. They're a
perfect match for CircuitPython!
You can drive 300 NeoPixel LEDs with brightness control (set
brightness=1.0
in object creation) and 1000 LEDs
without. That's because to adjust the brightness we have to dynamically recreate the data-stream each write.
You'll need the neopixel.mpy library if you don't already have it in your /lib folder! You can get it from the CircuitPython
Library Bundle (https://adafru.it/y8E) . If you need help installing the library, check out the CircuitPython Libraries
page (https://adafru.it/ABU) .
Wiring It Up
You'll need to solder up your NeoPixels first. Verify your connection is on the DATA INPUT or DIN side. Plugging into
the DATA OUT or DOUT side is a common mistake! The connections are labeled and some formats have arrows to
indicate the direction the data must flow.
For powering the pixels from the board, the 3.3V regulator output can handle about 500mA peak which is about 50
pixels with 'average' use. If you want really bright lights and a lot of pixels, we recommend powering direct from an
external power source.
On Gemma M0 and Circuit Playground Express this is the Vout pad - that pad has direct power from USB or the
battery, depending on which is higher voltage.
On Trinket M0, Feather M0 Express, Feather M4 Express, ItsyBitsy M0 Express and ItsyBitsy M4 Express the USB
or BAT pins will give you direct power from the USB port or battery.
On Metro M0 Express and Metro M4 Express, use the 5V pin regardless of whether it's powered via USB or the
DC jack.
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