Adafruit_NeoPixel.cpp

/*!
 * @file Adafruit_NeoPixel.cpp
 *
 * @mainpage Arduino Library for driving Adafruit NeoPixel addressable LEDs,
 * FLORA RGB Smart Pixels and compatible devicess -- WS2811, WS2812, WS2812B,
 * SK6812, etc.
 *
 * @section intro_sec Introduction
 *
 * This is the documentation for Adafruit's NeoPixel library for the
 * Arduino platform, allowing a broad range of microcontroller boards
 * (most AVR boards, many ARM devices, ESP8266 and ESP32, among others)
 * to control Adafruit NeoPixels, FLORA RGB Smart Pixels and compatible
 * devices -- WS2811, WS2812, WS2812B, SK6812, etc.
 *
 * Adafruit invests time and resources providing this open source code,
 * please support Adafruit and open-source hardware by purchasing products
 * from Adafruit!
 *
 * @section author Author
 *
 * Written by Phil "Paint Your Dragon" Burgess for Adafruit Industries,
 * with contributions by PJRC, Michael Miller and other members of the
 * open source community.
 *
 * @section license License
 *
 * This file is part of the Adafruit_NeoPixel library.
 *
 * Adafruit_NeoPixel is free software: you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * Adafruit_NeoPixel is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with NeoPixel. If not, see
 * <http://www.gnu.org/licenses/>.
 *
 */

#include "Adafruit_NeoPixel.h"

#if defined(TARGET_LPC1768)
  #include <time.h>
#endif

#if defined(NRF52) || defined(NRF52_SERIES)
#include "nrf.h"

// Interrupt is only disabled if there is no PWM device available
// Note: Adafruit Bluefruit nrf52 does not use this option
//#define NRF52_DISABLE_INT
#endif

/*!
  @brief   NeoPixel constructor when length, pin and pixel type are known
           at compile-time.
  @param   n  Number of NeoPixels in strand.
  @param   p  Arduino pin number which will drive the NeoPixel data in.
  @param   t  Pixel type -- add together NEO_* constants defined in
              Adafruit_NeoPixel.h, for example NEO_GRB+NEO_KHZ800 for
              NeoPixels expecting an 800 KHz (vs 400 KHz) data stream
              with color bytes expressed in green, red, blue order per
              pixel.
  @return  Adafruit_NeoPixel object. Call the begin() function before use.
*/
Adafruit_NeoPixel::Adafruit_NeoPixel(uint16_t n, uint16_t p, neoPixelType t) :
  begun(false), brightness(0), pixels(NULL), endTime(0) {
  updateType(t);
  updateLength(n);
  setPin(p);
}

/*!
  @brief   "Empty" NeoPixel constructor when length, pin and/or pixel type
           are not known at compile-time, and must be initialized later with
           updateType(), updateLength() and setPin().
  @return  Adafruit_NeoPixel object. Call the begin() function before use.
  @note    This function is deprecated, here only for old projects that
           may still be calling it. New projects should instead use the
           'new' keyword with the first constructor syntax (length, pin,
           type).
*/
Adafruit_NeoPixel::Adafruit_NeoPixel() :
#if defined(NEO_KHZ400)
  is800KHz(true),
#endif
  begun(false), numLEDs(0), numBytes(0), pin(-1), brightness(0), pixels(NULL),
  rOffset(1), gOffset(0), bOffset(2), wOffset(1), endTime(0) {
}

/*!
  @brief   Deallocate Adafruit_NeoPixel object, set data pin back to INPUT.
*/
Adafruit_NeoPixel::~Adafruit_NeoPixel() {
  free(pixels);
  if(pin >= 0) pinMode(pin, INPUT);
}

/*!
  @brief   Configure NeoPixel pin for output.
*/
void Adafruit_NeoPixel::begin(void) {
  if(pin >= 0) {
    pinMode(pin, OUTPUT);
    digitalWrite(pin, LOW);
  }
  begun = true;
}

/*!
  @brief   Change the length of a previously-declared Adafruit_NeoPixel
           strip object. Old data is deallocated and new data is cleared.
           Pin number and pixel format are unchanged.
  @param   n  New length of strip, in pixels.
  @note    This function is deprecated, here only for old projects that
           may still be calling it. New projects should instead use the
           'new' keyword with the first constructor syntax (length, pin,
           type).
*/
void Adafruit_NeoPixel::updateLength(uint16_t n) {
  free(pixels); // Free existing data (if any)

  // Allocate new data -- note: ALL PIXELS ARE CLEARED
  numBytes = n * ((wOffset == rOffset) ? 3 : 4);
  if((pixels = (uint8_t *)malloc(numBytes))) {
    memset(pixels, 0, numBytes);
    numLEDs = n;
  } else {
    numLEDs = numBytes = 0;
  }
}

/*!
  @brief   Change the pixel format of a previously-declared
           Adafruit_NeoPixel strip object. If format changes from one of
           the RGB variants to an RGBW variant (or RGBW to RGB), the old
           data will be deallocated and new data is cleared. Otherwise,
           the old data will remain in RAM and is not reordered to the
           new format, so it's advisable to follow up with clear().
  @param   t  Pixel type -- add together NEO_* constants defined in
              Adafruit_NeoPixel.h, for example NEO_GRB+NEO_KHZ800 for
              NeoPixels expecting an 800 KHz (vs 400 KHz) data stream
              with color bytes expressed in green, red, blue order per
              pixel.
  @note    This function is deprecated, here only for old projects that
           may still be calling it. New projects should instead use the
           'new' keyword with the first constructor syntax
           (length, pin, type).
*/
void Adafruit_NeoPixel::updateType(neoPixelType t) {
  bool oldThreeBytesPerPixel = (wOffset == rOffset); // false if RGBW

  wOffset = (t >> 6) & 0b11; // See notes in header file
  rOffset = (t >> 4) & 0b11; // regarding R/G/B/W offsets
  gOffset = (t >> 2) & 0b11;
  bOffset =  t       & 0b11;
#if defined(NEO_KHZ400)
  is800KHz = (t < 256);      // 400 KHz flag is 1<<8
#endif

  // If bytes-per-pixel has changed (and pixel data was previously
  // allocated), re-allocate to new size. Will clear any data.
  if(pixels) {
    bool newThreeBytesPerPixel = (wOffset == rOffset);
    if(newThreeBytesPerPixel != oldThreeBytesPerPixel) updateLength(numLEDs);
  }
}

#if defined(ESP8266)
// ESP8266 show() is external to enforce ICACHE_RAM_ATTR execution
extern "C" void ICACHE_RAM_ATTR espShow(
  uint16_t pin, uint8_t *pixels, uint32_t numBytes, uint8_t type);
#elif defined(ESP32)
extern "C" void espShow(
  uint16_t pin, uint8_t *pixels, uint32_t numBytes, uint8_t type);
#endif // ESP8266

#if defined(K210) 
#define KENDRYTE_K210 1
#endif

#if defined(KENDRYTE_K210)
extern "C" void  k210Show(
    uint8_t pin, uint8_t *pixels, uint32_t numBytes, boolean is800KHz);
#endif //KENDRYTE_K210
/*!
  @brief   Transmit pixel data in RAM to NeoPixels.
  @note    On most architectures, interrupts are temporarily disabled in
           order to achieve the correct NeoPixel signal timing. This means
           that the Arduino millis() and micros() functions, which require
           interrupts, will lose small intervals of time whenever this
           function is called (about 30 microseconds per RGB pixel, 40 for
           RGBW pixels). There's no easy fix for this, but a few
           specialized alternative or companion libraries exist that use
           very device-specific peripherals to work around it.
*/
void Adafruit_NeoPixel::show(void) {

  if(!pixels) return;

  // Data latch = 300+ microsecond pause in the output stream. Rather than
  // put a delay at the end of the function, the ending time is noted and
  // the function will simply hold off (if needed) on issuing the
  // subsequent round of data until the latch time has elapsed. This
  // allows the mainline code to start generating the next frame of data
  // rather than stalling for the latch.
  while(!canShow());
  // endTime is a private member (rather than global var) so that multiple
  // instances on different pins can be quickly issued in succession (each
  // instance doesn't delay the next).

  // In order to make this code runtime-configurable to work with any pin,
  // SBI/CBI instructions are eschewed in favor of full PORT writes via the
  // OUT or ST instructions. It relies on two facts: that peripheral
  // functions (such as PWM) take precedence on output pins, so our PORT-
  // wide writes won't interfere, and that interrupts are globally disabled
  // while data is being issued to the LEDs, so no other code will be
  // accessing the PORT. The code takes an initial 'snapshot' of the PORT
  // state, computes 'pin high' and 'pin low' values, and writes these back
  // to the PORT register as needed.

  // NRF52 may use PWM + DMA (if available), may not need to disable interrupt
#if !( defined(NRF52) || defined(NRF52_SERIES) )
  noInterrupts(); // Need 100% focus on instruction timing
#endif

#if defined(__AVR__)
// AVR MCUs -- ATmega & ATtiny (no XMEGA) ---------------------------------

  volatile uint16_t
    i   = numBytes; // Loop counter
  volatile uint8_t
   *ptr = pixels,   // Pointer to next byte
    b   = *ptr++,   // Current byte value
    hi,             // PORT w/output bit set high
    lo;             // PORT w/output bit set low

  // Hand-tuned assembly code issues data to the LED drivers at a specific
  // rate. There's separate code for different CPU speeds (8, 12, 16 MHz)
  // for both the WS2811 (400 KHz) and WS2812 (800 KHz) drivers. The
  // datastream timing for the LED drivers allows a little wiggle room each
  // way (listed in the datasheets), so the conditions for compiling each
  // case are set up for a range of frequencies rather than just the exact
  // 8, 12 or 16 MHz values, permitting use with some close-but-not-spot-on
  // devices (e.g. 16.5 MHz DigiSpark). The ranges were arrived at based
  // on the datasheet figures and have not been extensively tested outside
  // the canonical 8/12/16 MHz speeds; there's no guarantee these will work
  // close to the extremes (or possibly they could be pushed further).
  // Keep in mind only one CPU speed case actually gets compiled; the
  // resulting program isn't as massive as it might look from source here.

// 8 MHz(ish) AVR ---------------------------------------------------------
#if (F_CPU >= 7400000UL) && (F_CPU <= 9500000UL)

#if defined(NEO_KHZ400) // 800 KHz check needed only if 400 KHz support enabled
  if(is800KHz) {
#endif

    volatile uint8_t n1, n2 = 0;  // First, next bits out

    // Squeezing an 800 KHz stream out of an 8 MHz chip requires code
    // specific to each PORT register.

    // 10 instruction clocks per bit: HHxxxxxLLL
    // OUT instructions:              ^ ^    ^   (T=0,2,7)

    // PORTD OUTPUT ----------------------------------------------------

#if defined(PORTD)
 #if defined(PORTB) || defined(PORTC) || defined(PORTF)
    if(port == &PORTD) {
 #endif // defined(PORTB/C/F)

      hi = PORTD |  pinMask;
      lo = PORTD & ~pinMask;
      n1 = lo;
      if(b & 0x80) n1 = hi;

      // Dirty trick: RJMPs proceeding to the next instruction are used
      // to delay two clock cycles in one instruction word (rather than
      // using two NOPs). This was necessary in order to squeeze the
      // loop down to exactly 64 words -- the maximum possible for a
      // relative branch.

      asm volatile(
       "headD:"                   "\n\t" // Clk  Pseudocode
        // Bit 7:
        "out  %[port] , %[hi]"    "\n\t" // 1    PORT = hi
        "mov  %[n2]   , %[lo]"    "\n\t" // 1    n2   = lo
        "out  %[port] , %[n1]"    "\n\t" // 1    PORT = n1
        "rjmp .+0"                "\n\t" // 2    nop nop
        "sbrc %[byte] , 6"        "\n\t" // 1-2  if(b & 0x40)
         "mov %[n2]   , %[hi]"    "\n\t" // 0-1   n2 = hi
        "out  %[port] , %[lo]"    "\n\t" // 1    PORT = lo
        "rjmp .+0"                "\n\t" // 2    nop nop
        // Bit 6:
        "out  %[port] , %[hi]"    "\n\t" // 1    PORT = hi
        "mov  %[n1]   , %[lo]"    "\n\t" // 1    n1   = lo
        "out  %[port] , %[n2]"    "\n\t" // 1    PORT = n2
        "rjmp .+0"                "\n\t" // 2    nop nop
        "sbrc %[byte] , 5"        "\n\t" // 1-2  if(b & 0x20)
         "mov %[n1]   , %[hi]"    "\n\t" // 0-1   n1 = hi
        "out  %[port] , %[lo]"    "\n\t" // 1    PORT = lo
        "rjmp .+0"                "\n\t" // 2    nop nop
        // Bit 5:
        "out  %[port] , %[hi]"    "\n\t" // 1    PORT = hi
        "mov  %[n2]   , %[lo]"    "\n\t" // 1    n2   = lo
        "out  %[port] , %[n1]"    "\n\t" // 1    PORT = n1
        "rjmp .+0"                "\n\t" // 2    nop nop
        "sbrc %[byte] , 4"        "\n\t" // 1-2  if(b & 0x10)
         "mov %[n2]   , %[hi]"    "\n\t" // 0-1   n2 = hi
        "out  %[port] , %[lo]"    "\n\t" // 1    PORT = lo
        "rjmp .+0"                "\n\t" // 2    nop nop
        // Bit 4:
        "out  %[port] , %[hi]"    "\n\t" // 1    PORT = hi
        "mov  %[n1]   , %[lo]"    "\n\t" // 1    n1   = lo
        "out  %[port] , %[n2]"    "\n\t" // 1    PORT = n2
        "rjmp .+0"                "\n\t" // 2    nop nop
        "sbrc %[byte] , 3"        "\n\t" // 1-2  if(b & 0x08)
         "mov %[n1]   , %[hi]"    "\n\t" // 0-1   n1 = hi
        "out  %[port] , %[lo]"    "\n\t" // 1    PORT = lo
        "rjmp .+0"                "\n\t" // 2    nop nop
        // Bit 3:
        "out  %[port] , %[hi]"    "\n\t" // 1    PORT = hi
        "mov  %[n2]   , %[lo]"    "\n\t" // 1    n2   = lo
        "out  %[port] , %[n1]"    "\n\t" // 1    PORT = n1
        "rjmp .+0"                "\n\t" // 2    nop nop
        "sbrc %[byte] , 2"        "\n\t" // 1-2  if(b & 0x04)
         "mov %[n2]   , %[hi]"    "\n\t" // 0-1   n2 = hi
        "out  %[port] , %[lo]"    "\n\t" // 1    PORT = lo
        "rjmp .+0"                "\n\t" // 2    nop nop
        // Bit 2:
        "out  %[port] , %[hi]"    "\n\t" // 1    PORT = hi
        "mov  %[n1]   , %[lo]"    "\n\t" // 1    n1   = lo
        "out  %[port] , %[n2]"    "\n\t" // 1    PORT = n2
        "rjmp .+0"                "\n\t" // 2    nop nop
        "sbrc %[byte] , 1"        "\n\t" // 1-2  if(b & 0x02)
         "mov %[n1]   , %[hi]"    "\n\t" // 0-1   n1 = hi
        "out  %[port] , %[lo]"    "\n\t" // 1    PORT = lo
        "rjmp .+0"                "\n\t" // 2    nop nop
        // Bit 1:
        "out  %[port] , %[hi]"    "\n\t" // 1    PORT = hi
        "mov  %[n2]   , %[lo]"    "\n\t" // 1    n2   = lo
        "out  %[port] , %[n1]"    "\n\t" // 1    PORT = n1
        "rjmp .+0"                "\n\t" // 2    nop nop
        "sbrc %[byte] , 0"        "\n\t" // 1-2  if(b & 0x01)
         "mov %[n2]   , %[hi]"    "\n\t" // 0-1   n2 = hi
        "out  %[port] , %[lo]"    "\n\t" // 1    PORT = lo
        "sbiw %[count], 1"        "\n\t" // 2    i-- (don't act on Z flag yet)
        // Bit 0:
        "out  %[port] , %[hi]"    "\n\t" // 1    PORT = hi
        "mov  %[n1]   , %[lo]"    "\n\t" // 1    n1   = lo
        "out  %[port] , %[n2]"    "\n\t" // 1    PORT = n2
        "ld   %[byte] , %a[ptr]+" "\n\t" // 2    b = *ptr++
        "sbrc %[byte] , 7"        "\n\t" // 1-2  if(b & 0x80)
         "mov %[n1]   , %[hi]"    "\n\t" // 0-1   n1 = hi
        "out  %[port] , %[lo]"    "\n\t" // 1    PORT = lo
        "brne headD"              "\n"   // 2    while(i) (Z flag set above)
      : [byte]  "+r" (b),
        [n1]    "+r" (n1),
        [n2]    "+r" (n2),
        [count] "+w" (i)
      : [port]   "I" (_SFR_IO_ADDR(PORTD)),
        [ptr]    "e" (ptr),
        [hi]     "r" (hi),
        [lo]     "r" (lo));

 #if defined(PORTB) || defined(PORTC) || defined(PORTF)
    } else // other PORT(s)
 #endif // defined(PORTB/C/F)
#endif // defined(PORTD)

    // PORTB OUTPUT ----------------------------------------------------

#if defined(PORTB)
 #if defined(PORTD) || defined(PORTC) || defined(PORTF)
    if(port == &PORTB) {
 #endif // defined(PORTD/C/F)

      // Same as above, just switched to PORTB and stripped of comments.
      hi = PORTB |  pinMask;
      lo = PORTB & ~pinMask;
      n1 = lo;
      if(b & 0x80) n1 = hi;

      asm volatile(
       "headB:"                   "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n2]   , %[lo]"    "\n\t"
        "out  %[port] , %[n1]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 6"        "\n\t"
         "mov %[n2]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n1]   , %[lo]"    "\n\t"
        "out  %[port] , %[n2]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 5"        "\n\t"
         "mov %[n1]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n2]   , %[lo]"    "\n\t"
        "out  %[port] , %[n1]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 4"        "\n\t"
         "mov %[n2]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n1]   , %[lo]"    "\n\t"
        "out  %[port] , %[n2]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 3"        "\n\t"
         "mov %[n1]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n2]   , %[lo]"    "\n\t"
        "out  %[port] , %[n1]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 2"        "\n\t"
         "mov %[n2]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n1]   , %[lo]"    "\n\t"
        "out  %[port] , %[n2]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 1"        "\n\t"
         "mov %[n1]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n2]   , %[lo]"    "\n\t"
        "out  %[port] , %[n1]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 0"        "\n\t"
         "mov %[n2]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "sbiw %[count], 1"        "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n1]   , %[lo]"    "\n\t"
        "out  %[port] , %[n2]"    "\n\t"
        "ld   %[byte] , %a[ptr]+" "\n\t"
        "sbrc %[byte] , 7"        "\n\t"
         "mov %[n1]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "brne headB"              "\n"
      : [byte] "+r" (b), [n1] "+r" (n1), [n2] "+r" (n2), [count] "+w" (i)
      : [port] "I" (_SFR_IO_ADDR(PORTB)), [ptr] "e" (ptr), [hi] "r" (hi),
        [lo] "r" (lo));

 #if defined(PORTD) || defined(PORTC) || defined(PORTF)
    }
 #endif
 #if defined(PORTC) || defined(PORTF)
    else
 #endif // defined(PORTC/F)
#endif // defined(PORTB)

    // PORTC OUTPUT ----------------------------------------------------

#if defined(PORTC)
 #if defined(PORTD) || defined(PORTB) || defined(PORTF)
    if(port == &PORTC) {
 #endif // defined(PORTD/B/F)

      // Same as above, just switched to PORTC and stripped of comments.
      hi = PORTC |  pinMask;
      lo = PORTC & ~pinMask;
      n1 = lo;
      if(b & 0x80) n1 = hi;

      asm volatile(
       "headC:"                   "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n2]   , %[lo]"    "\n\t"
        "out  %[port] , %[n1]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 6"        "\n\t"
         "mov %[n2]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n1]   , %[lo]"    "\n\t"
        "out  %[port] , %[n2]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 5"        "\n\t"
         "mov %[n1]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n2]   , %[lo]"    "\n\t"
        "out  %[port] , %[n1]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 4"        "\n\t"
         "mov %[n2]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n1]   , %[lo]"    "\n\t"
        "out  %[port] , %[n2]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 3"        "\n\t"
         "mov %[n1]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n2]   , %[lo]"    "\n\t"
        "out  %[port] , %[n1]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 2"        "\n\t"
         "mov %[n2]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n1]   , %[lo]"    "\n\t"
        "out  %[port] , %[n2]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 1"        "\n\t"
         "mov %[n1]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n2]   , %[lo]"    "\n\t"
        "out  %[port] , %[n1]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 0"        "\n\t"
         "mov %[n2]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "sbiw %[count], 1"        "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n1]   , %[lo]"    "\n\t"
        "out  %[port] , %[n2]"    "\n\t"
        "ld   %[byte] , %a[ptr]+" "\n\t"
        "sbrc %[byte] , 7"        "\n\t"
         "mov %[n1]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "brne headC"              "\n"
      : [byte] "+r" (b), [n1] "+r" (n1), [n2] "+r" (n2), [count] "+w" (i)
      : [port] "I" (_SFR_IO_ADDR(PORTC)), [ptr] "e" (ptr), [hi] "r" (hi),
        [lo] "r" (lo));

 #if defined(PORTD) || defined(PORTB) || defined(PORTF)
    }
 #endif // defined(PORTD/B/F)
 #if defined(PORTF)
    else
 #endif
#endif // defined(PORTC)

    // PORTF OUTPUT ----------------------------------------------------

#if defined(PORTF)
 #if defined(PORTD) || defined(PORTB) || defined(PORTC)
    if(port == &PORTF) {
 #endif // defined(PORTD/B/C)

      hi = PORTF |  pinMask;
      lo = PORTF & ~pinMask;
      n1 = lo;
      if(b & 0x80) n1 = hi;

      asm volatile(
       "headF:"                   "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n2]   , %[lo]"    "\n\t"
        "out  %[port] , %[n1]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 6"        "\n\t"
         "mov %[n2]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n1]   , %[lo]"    "\n\t"
        "out  %[port] , %[n2]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 5"        "\n\t"
         "mov %[n1]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n2]   , %[lo]"    "\n\t"
        "out  %[port] , %[n1]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 4"        "\n\t"
         "mov %[n2]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n1]   , %[lo]"    "\n\t"
        "out  %[port] , %[n2]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 3"        "\n\t"
         "mov %[n1]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n2]   , %[lo]"    "\n\t"
        "out  %[port] , %[n1]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 2"        "\n\t"
         "mov %[n2]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n1]   , %[lo]"    "\n\t"
        "out  %[port] , %[n2]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 1"        "\n\t"
         "mov %[n1]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n2]   , %[lo]"    "\n\t"
        "out  %[port] , %[n1]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "sbrc %[byte] , 0"        "\n\t"
         "mov %[n2]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "sbiw %[count], 1"        "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "mov  %[n1]   , %[lo]"    "\n\t"
        "out  %[port] , %[n2]"    "\n\t"
        "ld   %[byte] , %a[ptr]+" "\n\t"
        "sbrc %[byte] , 7"        "\n\t"
         "mov %[n1]   , %[hi]"    "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "brne headF"              "\n"
      : [byte] "+r" (b), [n1] "+r" (n1), [n2] "+r" (n2), [count] "+w" (i)
      : [port] "I" (_SFR_IO_ADDR(PORTF)), [ptr] "e" (ptr), [hi] "r" (hi),
        [lo] "r" (lo));

 #if defined(PORTD) || defined(PORTB) || defined(PORTC)
    }
 #endif // defined(PORTD/B/C)
#endif // defined(PORTF)

#if defined(NEO_KHZ400)
  } else { // end 800 KHz, do 400 KHz

    // Timing is more relaxed; unrolling the inner loop for each bit is
    // not necessary. Still using the peculiar RJMPs as 2X NOPs, not out
    // of need but just to trim the code size down a little.
    // This 400-KHz-datastream-on-8-MHz-CPU code is not quite identical
    // to the 800-on-16 code later -- the hi/lo timing between WS2811 and
    // WS2812 is not simply a 2:1 scale!

    // 20 inst. clocks per bit: HHHHxxxxxxLLLLLLLLLL
    // ST instructions:         ^   ^     ^          (T=0,4,10)

    volatile uint8_t next, bit;

    hi   = *port |  pinMask;
    lo   = *port & ~pinMask;
    next = lo;
    bit  = 8;

    asm volatile(
     "head20:"                  "\n\t" // Clk  Pseudocode    (T =  0)
      "st   %a[port], %[hi]"    "\n\t" // 2    PORT = hi     (T =  2)
      "sbrc %[byte] , 7"        "\n\t" // 1-2  if(b & 128)
       "mov  %[next], %[hi]"    "\n\t" // 0-1   next = hi    (T =  4)
      "st   %a[port], %[next]"  "\n\t" // 2    PORT = next   (T =  6)
      "mov  %[next] , %[lo]"    "\n\t" // 1    next = lo     (T =  7)
      "dec  %[bit]"             "\n\t" // 1    bit--         (T =  8)
      "breq nextbyte20"         "\n\t" // 1-2  if(bit == 0)
      "rol  %[byte]"            "\n\t" // 1    b <<= 1       (T = 10)
      "st   %a[port], %[lo]"    "\n\t" // 2    PORT = lo     (T = 12)
      "rjmp .+0"                "\n\t" // 2    nop nop       (T = 14)
      "rjmp .+0"                "\n\t" // 2    nop nop       (T = 16)
      "rjmp .+0"                "\n\t" // 2    nop nop       (T = 18)
      "rjmp head20"             "\n\t" // 2    -> head20 (next bit out)
     "nextbyte20:"              "\n\t" //                    (T = 10)
      "st   %a[port], %[lo]"    "\n\t" // 2    PORT = lo     (T = 12)
      "nop"                     "\n\t" // 1    nop           (T = 13)
      "ldi  %[bit]  , 8"        "\n\t" // 1    bit = 8       (T = 14)
      "ld   %[byte] , %a[ptr]+" "\n\t" // 2    b = *ptr++    (T = 16)
      "sbiw %[count], 1"        "\n\t" // 2    i--           (T = 18)
      "brne head20"             "\n"   // 2    if(i != 0) -> (next byte)
      : [port]  "+e" (port),
        [byte]  "+r" (b),
        [bit]   "+r" (bit),
        [next]  "+r" (next),
        [count] "+w" (i)
      : [hi]    "r" (hi),
        [lo]    "r" (lo),
        [ptr]   "e" (ptr));
  }
#endif // NEO_KHZ400

// 12 MHz(ish) AVR --------------------------------------------------------
#elif (F_CPU >= 11100000UL) && (F_CPU <= 14300000UL)

#if defined(NEO_KHZ400) // 800 KHz check needed only if 400 KHz support enabled
  if(is800KHz) {
#endif

    // In the 12 MHz case, an optimized 800 KHz datastream (no dead time
    // between bytes) requires a PORT-specific loop similar to the 8 MHz
    // code (but a little more relaxed in this case).

    // 15 instruction clocks per bit: HHHHxxxxxxLLLLL
    // OUT instructions:              ^   ^     ^     (T=0,4,10)

    volatile uint8_t next;

    // PORTD OUTPUT ----------------------------------------------------

#if defined(PORTD)
 #if defined(PORTB) || defined(PORTC) || defined(PORTF)
    if(port == &PORTD) {
 #endif // defined(PORTB/C/F)

      hi   = PORTD |  pinMask;
      lo   = PORTD & ~pinMask;
      next = lo;
      if(b & 0x80) next = hi;

      // Don't "optimize" the OUT calls into the bitTime subroutine;
      // we're exploiting the RCALL and RET as 3- and 4-cycle NOPs!
      asm volatile(
       "headD:"                   "\n\t" //        (T =  0)
        "out   %[port], %[hi]"    "\n\t" //        (T =  1)
        "rcall bitTimeD"          "\n\t" // Bit 7  (T = 15)
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeD"          "\n\t" // Bit 6
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeD"          "\n\t" // Bit 5
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeD"          "\n\t" // Bit 4
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeD"          "\n\t" // Bit 3
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeD"          "\n\t" // Bit 2
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeD"          "\n\t" // Bit 1
        // Bit 0:
        "out  %[port] , %[hi]"    "\n\t" // 1    PORT = hi    (T =  1)
        "rjmp .+0"                "\n\t" // 2    nop nop      (T =  3)
        "ld   %[byte] , %a[ptr]+" "\n\t" // 2    b = *ptr++   (T =  5)
        "out  %[port] , %[next]"  "\n\t" // 1    PORT = next  (T =  6)
        "mov  %[next] , %[lo]"    "\n\t" // 1    next = lo    (T =  7)
        "sbrc %[byte] , 7"        "\n\t" // 1-2  if(b & 0x80) (T =  8)
         "mov %[next] , %[hi]"    "\n\t" // 0-1    next = hi  (T =  9)
        "nop"                     "\n\t" // 1                 (T = 10)
        "out  %[port] , %[lo]"    "\n\t" // 1    PORT = lo    (T = 11)
        "sbiw %[count], 1"        "\n\t" // 2    i--          (T = 13)
        "brne headD"              "\n\t" // 2    if(i != 0) -> (next byte)
         "rjmp doneD"             "\n\t"
        "bitTimeD:"               "\n\t" //      nop nop nop     (T =  4)
         "out  %[port], %[next]"  "\n\t" // 1    PORT = next     (T =  5)
         "mov  %[next], %[lo]"    "\n\t" // 1    next = lo       (T =  6)
         "rol  %[byte]"           "\n\t" // 1    b <<= 1         (T =  7)
         "sbrc %[byte], 7"        "\n\t" // 1-2  if(b & 0x80)    (T =  8)
          "mov %[next], %[hi]"    "\n\t" // 0-1   next = hi      (T =  9)
         "nop"                    "\n\t" // 1                    (T = 10)
         "out  %[port], %[lo]"    "\n\t" // 1    PORT = lo       (T = 11)
         "ret"                    "\n\t" // 4    nop nop nop nop (T = 15)
         "doneD:"                 "\n"
        : [byte]  "+r" (b),
          [next]  "+r" (next),
          [count] "+w" (i)
        : [port]   "I" (_SFR_IO_ADDR(PORTD)),
          [ptr]    "e" (ptr),
          [hi]     "r" (hi),
          [lo]     "r" (lo));

 #if defined(PORTB) || defined(PORTC) || defined(PORTF)
    } else // other PORT(s)
 #endif // defined(PORTB/C/F)
#endif // defined(PORTD)

    // PORTB OUTPUT ----------------------------------------------------

#if defined(PORTB)
 #if defined(PORTD) || defined(PORTC) || defined(PORTF)
    if(port == &PORTB) {
 #endif // defined(PORTD/C/F)

      hi   = PORTB |  pinMask;
      lo   = PORTB & ~pinMask;
      next = lo;
      if(b & 0x80) next = hi;

      // Same as above, just set for PORTB & stripped of comments
      asm volatile(
       "headB:"                   "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeB"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeB"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeB"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeB"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeB"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeB"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeB"          "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "ld   %[byte] , %a[ptr]+" "\n\t"
        "out  %[port] , %[next]"  "\n\t"
        "mov  %[next] , %[lo]"    "\n\t"
        "sbrc %[byte] , 7"        "\n\t"
         "mov %[next] , %[hi]"    "\n\t"
        "nop"                     "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "sbiw %[count], 1"        "\n\t"
        "brne headB"              "\n\t"
         "rjmp doneB"             "\n\t"
        "bitTimeB:"               "\n\t"
         "out  %[port], %[next]"  "\n\t"
         "mov  %[next], %[lo]"    "\n\t"
         "rol  %[byte]"           "\n\t"
         "sbrc %[byte], 7"        "\n\t"
          "mov %[next], %[hi]"    "\n\t"
         "nop"                    "\n\t"
         "out  %[port], %[lo]"    "\n\t"
         "ret"                    "\n\t"
         "doneB:"                 "\n"
        : [byte] "+r" (b), [next] "+r" (next), [count] "+w" (i)
        : [port] "I" (_SFR_IO_ADDR(PORTB)), [ptr] "e" (ptr), [hi] "r" (hi),
          [lo] "r" (lo));

 #if defined(PORTD) || defined(PORTC) || defined(PORTF)
    }
 #endif
 #if defined(PORTC) || defined(PORTF)
    else
 #endif // defined(PORTC/F)
#endif // defined(PORTB)

    // PORTC OUTPUT ----------------------------------------------------

#if defined(PORTC)
 #if defined(PORTD) || defined(PORTB) || defined(PORTF)
    if(port == &PORTC) {
 #endif // defined(PORTD/B/F)

      hi   = PORTC |  pinMask;
      lo   = PORTC & ~pinMask;
      next = lo;
      if(b & 0x80) next = hi;

      // Same as above, just set for PORTC & stripped of comments
      asm volatile(
       "headC:"                   "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "ld   %[byte] , %a[ptr]+" "\n\t"
        "out  %[port] , %[next]"  "\n\t"
        "mov  %[next] , %[lo]"    "\n\t"
        "sbrc %[byte] , 7"        "\n\t"
         "mov %[next] , %[hi]"    "\n\t"
        "nop"                     "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "sbiw %[count], 1"        "\n\t"
        "brne headC"              "\n\t"
         "rjmp doneC"             "\n\t"
        "bitTimeC:"               "\n\t"
         "out  %[port], %[next]"  "\n\t"
         "mov  %[next], %[lo]"    "\n\t"
         "rol  %[byte]"           "\n\t"
         "sbrc %[byte], 7"        "\n\t"
          "mov %[next], %[hi]"    "\n\t"
         "nop"                    "\n\t"
         "out  %[port], %[lo]"    "\n\t"
         "ret"                    "\n\t"
         "doneC:"                 "\n"
        : [byte] "+r" (b), [next] "+r" (next), [count] "+w" (i)
        : [port] "I" (_SFR_IO_ADDR(PORTC)), [ptr] "e" (ptr), [hi] "r" (hi),
          [lo] "r" (lo));

 #if defined(PORTD) || defined(PORTB) || defined(PORTF)
    }
 #endif // defined(PORTD/B/F)
 #if defined(PORTF)
    else
 #endif
#endif // defined(PORTC)

    // PORTF OUTPUT ----------------------------------------------------

#if defined(PORTF)
 #if defined(PORTD) || defined(PORTB) || defined(PORTC)
    if(port == &PORTF) {
 #endif // defined(PORTD/B/C)

      hi   = PORTF |  pinMask;
      lo   = PORTF & ~pinMask;
      next = lo;
      if(b & 0x80) next = hi;

      // Same as above, just set for PORTF & stripped of comments
      asm volatile(
       "headF:"                   "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out   %[port], %[hi]"    "\n\t"
        "rcall bitTimeC"          "\n\t"
        "out  %[port] , %[hi]"    "\n\t"
        "rjmp .+0"                "\n\t"
        "ld   %[byte] , %a[ptr]+" "\n\t"
        "out  %[port] , %[next]"  "\n\t"
        "mov  %[next] , %[lo]"    "\n\t"
        "sbrc %[byte] , 7"        "\n\t"
         "mov %[next] , %[hi]"    "\n\t"
        "nop"                     "\n\t"
        "out  %[port] , %[lo]"    "\n\t"
        "sbiw %[count], 1"        "\n\t"
        "brne headF"              "\n\t"
         "rjmp doneC"             "\n\t"
        "bitTimeC:"               "\n\t"
         "out  %[port], %[next]"  "\n\t"
         "mov  %[next], %[lo]"    "\n\t"
         "rol  %[byte]"           "\n\t"
         "sbrc %[byte], 7"        "\n\t"
          "mov %[next], %[hi]"    "\n\t"
         "nop"                    "\n\t"
         "out  %[port], %[lo]"    "\n\t"
         "ret"                    "\n\t"
         "doneC:"                 "\n"
        : [byte] "+r" (b), [next] "+r" (next), [count] "+w" (i)
        : [port] "I" (_SFR_IO_ADDR(PORTF)), [ptr] "e" (ptr), [hi] "r" (hi),
          [lo] "r" (lo));

 #if defined(PORTD) || defined(PORTB) || defined(PORTC)
    }
 #endif // defined(PORTD/B/C)
#endif // defined(PORTF)

#if defined(NEO_KHZ400)
  } else { // 400 KHz

    // 30 instruction clocks per bit: HHHHHHxxxxxxxxxLLLLLLLLLLLLLLL
    // ST instructions:               ^     ^        ^    (T=0,6,15)

    volatile uint8_t next, bit;

    hi   = *port |  pinMask;
    lo   = *port & ~pinMask;
    next = lo;
    bit  = 8;

    asm volatile(
     "head30:"                  "\n\t" // Clk  Pseudocode    (T =  0)
      "st   %a[port], %[hi]"    "\n\t" // 2    PORT = hi     (T =  2)
      "sbrc %[byte] , 7"        "\n\t" // 1-2  if(b & 128)
       "mov  %[next], %[hi]"    "\n\t" // 0-1   next = hi    (T =  4)
      "rjmp .+0"                "\n\t" // 2    nop nop       (T =  6)
      "st   %a[port], %[next]"  "\n\t" // 2    PORT = next   (T =  8)
      "rjmp .+0"                "\n\t" // 2    nop nop       (T = 10)
      "rjmp .+0"                "\n\t" // 2    nop nop       (T = 12)
      "rjmp .+0"                "\n\t" // 2    nop nop       (T = 14)
      "nop"                     "\n\t" // 1    nop           (T = 15)
      "st   %a[port], %[lo]"    "\n\t" // 2    PORT = lo     (T = 17)
      "rjmp .+0"                "\n\t" // 2    nop nop       (T = 19)
      "dec  %[bit]"             "\n\t" // 1    bit--         (T = 20)
      "breq nextbyte30"         "\n\t" // 1-2  if(bit == 0)
      "rol  %[byte]"            "\n\t" // 1    b <<= 1       (T = 22)
      "rjmp .+0"                "\n\t" // 2    nop nop       (T = 24)
      "rjmp .+0"                "\n\t" // 2    nop nop       (T = 26)
      "rjmp .+0"                "\n\t" // 2    nop nop       (T = 28)