Created ESP32 and RTOS Tasks (markdown)

ESP32-and-RTOS-Tasks.md

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+On ESP32, when the CPU is loaded, asynchronous WiFi libraries (like ESPAsyncWebServer or async-mqtt-client) may interfere with interrupts used to control the LEDs (I2S mode is less affected by this), which causes flickering of LEDs.
+
+One way to solve that is to create a high priority task that will take care of showing the LEDs.
+
+The following code is an example of this approach:
+
+```cpp
+xSemaphoreHandle semaphore = NULL;
+TaskHandle_t commit_task;
+NeoPixelBus<NeoGrbFeature, NeoEsp32RmtNWs2811Method> pixel_bus;
+
+void commitTaskProcedure(void *arg)
+{
+    while (true)
+    {
+        while (ulTaskNotifyTake(pdTRUE, portMAX_DELAY) != 1)
+            ;
+        pixel_bus.Show();
+        while (!pixel_bus.CanShow())
+            ;
+        xSemaphoreGive(semaphore);
+    }
+}
+
+void commit()
+{
+    xTaskNotifyGive(commit_task);
+    while (xSemaphoreTake(semaphore, portMAX_DELAY) != pdTRUE)
+        ;
+}
+
+void init_task()
+{
+    commit_task = NULL;
+    semaphore = xSemaphoreCreateBinary();
+
+    xTaskCreatePinnedToCore(
+        commitTaskProcedure,         /* Task function. */
+        "ShowRunnerTask",            /* name of task. */
+        10000,                       /* Stack size of task */
+        NULL,                        /* parameter of the task */
+        4,                           /* priority of the task */
+        &commit_task,                /* Task handle to keep track of created task */
+        1);                          /* pin task to core core_id */
+}
+
+void setup()
+{
+   pixel_bus.begin();
+   init_task();
+}
+
+void loop()
+{
+    commit();
+    delay(10);
+}
+```