Here is a bit of code I got running for an LED strip using the Adafruit_NeoPixel library. The code is written for an ESP32 so ignore the esp32 stuff, the principle remains the same.
There are two main tasks (functions) void fDo_LEDs( ) and void fDo_AudioReadFreq(). The last instruction in setup() starts the task void fDo_AudioReadFreq() to do a data read. At task creation the fDo_LEDs( ) stops and waits for data to become available, processes the data, triggers fDo_AudioReadFreq(), and goes back to waiting for the arrival of new data to process.
Quite speedy.
#include "esp_system.h" //This inclusion configures the peripherals in the ESP system.
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/timers.h"
#include "freertos/event_groups.h"
#include <Adafruit_NeoPixel.h>
#include "AudioAnalyzer.h"
////
/* define event group and event bits */
EventGroupHandle_t eg;
#define evtDo_AudioReadFreq ( 1 << 0 ) // 1
////
TickType_t xTicksToWait0 = 0;
////
QueueHandle_t xQ_LED_Info;
////
const int NeoPixelPin = 26;
const int LED_COUNT = 24; //total number of leds in the strip
const int NOISE = 10; // noise that you want to chop off
const int SEG = 6; // how many parts you want to separate the led strip into
// const int SerialDataBits = 115200;
const int Priority4 = 4;
const int TaskStack40K = 40000;
const int TaskCore1 = 1;
const int TaskCore0 = 0;
const int AudioSampleSize = 6;
const int Brightness = 180;
const int A_D_ConversionBits = 4096; // arduino use 1024, ESP32 use 4096
////
Analyzer Audio = Analyzer( 5, 15, 36 );//Strobe pin ->15 RST pin ->2 Analog Pin ->36
// When we setup the NeoPixel library, we tell it how many pixels, and which pin to use to send signals.
Adafruit_NeoPixel leds = Adafruit_NeoPixel( LED_COUNT, NeoPixelPin, NEO_GRB + NEO_KHZ800 );
////
int FreqVal[7];//create an array to store the value of different freq
////
void setup()
{
eg = xEventGroupCreate();
// Serial.begin( SerialDataBits );
Audio.Init(); // start the audio analyzer
leds.begin(); // Call this to start up the LED strip.
clearLEDs(); // This function, defined below, de-energizes all LEDs...
leds.show(); // ...but the LEDs don't actually update until you call this.
////
xQ_LED_Info = xQueueCreate ( 1, sizeof(FreqVal) );
//////////////////////////////////////////////////////////////////////////////////////////////
xTaskCreatePinnedToCore( fDo_AudioReadFreq, "fDo_ AudioReadFreq", TaskStack40K, NULL, Priority4, NULL, TaskCore1 ); //assigned to core
xTaskCreatePinnedToCore( fDo_LEDs, "fDo_ LEDs", TaskStack40K, NULL, Priority4, NULL, TaskCore0 ); //assigned to core
xEventGroupSetBits( eg, evtDo_AudioReadFreq );
} // setup()
////
void loop() {} // void loop
////
void fDo_LEDs( void *pvParameters )
{
int iFreqVal[7];
int j;
leds.setBrightness( Brightness ); // 1 = min brightness (off), 255 = max brightness.
for (;;)
{
if (xQueueReceive( xQ_LED_Info, &iFreqVal, portMAX_DELAY) == pdTRUE)
{
j = 0;
//assign different values for different parts of the led strip
for (j = 0; j < LED_COUNT; j++)
{
if ( (0 <= j) && (j < (LED_COUNT / SEG)) )
{
set(j, iFreqVal[0]); // set the color of led
}
else if ( ((LED_COUNT / SEG) <= j) && (j < (LED_COUNT / SEG * 2)) )
{
set(j, iFreqVal[1]); //orginal code
}
else if ( ((LED_COUNT / SEG * 2) <= j) && (j < (LED_COUNT / SEG * 3)) )
{
set(j, iFreqVal[2]);
}
else if ( ((LED_COUNT / SEG * 3) <= j) && (j < (LED_COUNT / SEG * 4)) )
{
set(j, iFreqVal[3]);
}
else if ( ((LED_COUNT / SEG * 4) <= j) && (j < (LED_COUNT / SEG * 5)) )
{
set(j, iFreqVal[4]);
}
else
{
set(j, iFreqVal[5]);
}
}
leds.show();
}
xEventGroupSetBits( eg, evtDo_AudioReadFreq );
}
vTaskDelete( NULL );
} // void fDo_ LEDs( void *pvParameters )
////
void fDo_AudioReadFreq( void *pvParameters )
{
// int64_t EndTime = esp_timer_get_time();
// int64_t StartTime = esp_timer_get_time(); //gets time in uSeconds like Arduino Micros.
for (;;)
{
xEventGroupWaitBits (eg, evtDo_AudioReadFreq, pdTRUE, pdTRUE, portMAX_DELAY);
// EndTime = esp_timer_get_time() - StartTime;
// log_i( "TimeSpentOnTasks: %d", EndTime );
Audio.ReadFreq(FreqVal);
for (int i = 0; i < 7; i++)
{
FreqVal[i] = constrain( FreqVal[i], NOISE, A_D_ConversionBits );
FreqVal[i] = map( FreqVal[i], NOISE, A_D_ConversionBits, 0, 255 );
log_i( "Freq %d Value: %d", i, FreqVal[i]);//used for debugging and Freq choosing
}
xQueueSend( xQ_LED_Info, ( void * ) &FreqVal, xTicksToWait0 );
// StartTime = esp_timer_get_time();
}
vTaskDelete( NULL );
} // fDo_ AudioReadFreq( void *pvParameters )
////
//the following function set the led color based on its position and freq value
void set(byte position, int value)
{
// segment 0, red
if ( (0 <= position) && (position < LED_COUNT / SEG) ) // segment 0 (bottom to top), red
{
if ( value == 0 )
{
leds.setPixelColor( position, 0, 0, 0 );
}
else
{
leds.setPixelColor( position, leds.Color( value , 0, 0) );
}
}
else if ( (LED_COUNT / SEG <= position) && (position < LED_COUNT / SEG * 2) ) // segment 1 yellow
{
if ( value == 0 )
{
leds.setPixelColor(position, leds.Color(0, 0, 0));
}
else
{
leds.setPixelColor(position, leds.Color( value, value, 0)); // works better to make yellow
}
}
else if ( (LED_COUNT / SEG * 2 <= position) && (position < LED_COUNT / SEG * 3) ) // segment 2 pink
{
if ( value == 0 )
{
leds.setPixelColor(position, leds.Color(0, 0, 0));
}
else
{
leds.setPixelColor(position, leds.Color( value, 0, value * .91) ); // pink
}
}
else if ( (LED_COUNT / SEG * 3 <= position) && (position < LED_COUNT / SEG * 4) ) // seg 3, green
{
if ( value == 0 )
{
leds.setPixelColor(position, leds.Color( 0, 0, 0));
}
else //
{
leds.setPixelColor( position, leds.Color( 0, value, 0) ); //
}
}
else if ( (LED_COUNT / SEG * 4 <= position) && (position < LED_COUNT / SEG * 5) ) // segment 4, leds.color( R, G, B ), blue
{
// Serial.println( position );
if ( value == 0 )
{
leds.setPixelColor(position, leds.Color( 0, 0, 0));
}
else //
{
leds.setPixelColor(position, leds.Color( 0, 0, value) ); // blue
}
}
else // segment 5
{
if ( value == 0 )
{
leds.setPixelColor(position, leds.Color( 0, 0, 0)); // only helps a little bit in turning the leds off
}
else
{
leds.setPixelColor( position, leds.Color( value, value * .3, 0) ); // orange
}
}
} // void set(byte position, int value)
////
void clearLEDs()
{
for (int i = 0; i < LED_COUNT; i++)
{
leds.setPixelColor(i, 0);
}
} // void clearLEDs()
The function leds.setPixelColor() takes in 3 values to make color. The value numbers quantity is also relevant to light intensity produced.
If you look up the color code of orange, rgb(255,165,0), a ratio can be had to create orange light.
I vary the intensity of orange by leds.setPixelColor( position, leds.Color( value, value * .3, 0) ); which changes the light intensity of orange, based upon value for red, a percentage of the value for green, and 0 for blue. Here you can see how I use a bit-o-math to make changing intensity pink light with leds.setPixelColor(position, leds.Color( value, 0, value * .91) );
Hope that makes sense. You can fade by using just leds.setPixelColor.
