// Copyright 2017 The Periph Authors. All rights reserved.
// Use of this source code is governed under the Apache License, Version 2.0
// that can be found in the LICENSE file.

// Package nrzled is a driver for LEDs ws2811/ws2812/ws2812b and compatible
// devices like sk6812 and ucs1903 that uses a single wire NRZ encoded
// communication protocol.
//
// Note that some ICs are 7 bits with the least significant bit ignored, others
// are using a real 8 bits PWM. The PWM frequency varies across ICs.
// User can select a driver implementation using a memory-mapped GPIO line
// or leverage a SPI connection's MISO pin.
//
// The SPI implementation is sensitive to variations in SPI clock speed.
// On the Raspberry Pi, you will need to add `core_freq=250`
// to /boot/config.txt to prevent glitching.
//
// You may also need to increase your SPI buffer size to 12*num_pixels+3, or just max it out
// with `spidev.bufsize=65536`. That should allopw you to buffer over 5400 Neopixels.
//
// Datasheet
//
// This directory contains datasheets for ws2812, ws2812b, ucs190x and various
// sk6812.
//
// https://github.com/cpldcpu/light_ws2812/tree/master/Datasheets
//
// UCS1903 datasheet
//
// http://www.bestlightingbuy.com/pdf/UCS1903%20datasheet.pdf
//
// ws2812b A.K.A. Neopixel datasheet
//
// https://cdn-shop.adafruit.com/datasheets/WS2812B.pdf
package nrzled