Delay code written for Arduino was no longer quite right and prone to overflow

On ESP32 we can use 64bits and the native libraries and it's OK

Author: bbulkow

components/FastLED-idf/fastled_delay.h

@@ -1,6 +1,11 @@
 #ifndef __INC_FL_DELAY_H
 #define __INC_FL_DELAY_H
 
+
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "esp_timer.h"
+
 #include "FastLED.h"
 
 ///@file fastled_delay.h
@@ -11,18 +16,29 @@ FASTLED_NAMESPACE_BEGIN
 /// Class to ensure that a minimum amount of time has kicked since the last time run - and delay if not enough time has passed yet
 /// this should make sure that chipsets that have
 template<int WAIT> class CMinWait {
-	uint16_t mLastMicros;
+	uint64_t mLastMicros;
 public:
 	CMinWait() { mLastMicros = 0; }
 
 	void wait() {
-		uint16_t diff;
-		do {
-			diff = (micros() & 0xFFFF) - mLastMicros;
-		} while(diff < WAIT);
+		// how long I been waiting
+		uint64_t waited = esp_timer_get_time() - mLastMicros;
+		// fast path, waited long enough
+		if (waited >= WAIT) return;
+		// delay vs spin
+		if ((WAIT - waited) > (portTICK_PERIOD_MS * 1000)) {
+			int tickDelay = ((WAIT - waited) / 1000) / portTICK_PERIOD_MS;
+			//printf("cMinWait: %llu micros means delay %d ticks\n",(WAIT - waited),tickDelay);
+			vTaskDelay( tickDelay );
+		}
+		else { /*buzz is only other option outch */
+			do {
+				waited = esp_timer_get_time() - mLastMicros;
+			} while( waited > WAIT);
+		}
 	}
 
-	void mark() { mLastMicros = micros() & 0xFFFF; }
+	void mark() { mLastMicros = esp_timer_get_time(); }
 };
 
 

components/FastLED-idf/platforms/esp/32/clockless_i2s_esp32.h

@@ -205,7 +205,7 @@ class ClocklessController : public CPixelLEDController<RGB_ORDER>
     PixelController<RGB_ORDER> * mPixels;
 
     // -- Make sure we can't call show() too quickly
-    CMinWait<50>   mWait;
+    CMinWait<55>   mWait;
 
  public:
 

components/FastLED-idf/platforms/esp/32/clockless_rmt_esp32.cpp

@@ -31,7 +31,7 @@ static intr_handle_t gRMT_intr_handle = NULL;
 static xSemaphoreHandle gTX_sem = NULL;
 
 // -- Make sure we can't call show() too quickly (fastled library)
-CMinWait<50>   gWait;
+CMinWait<55>   gWait;
 
 static bool gInitialized = false;
 
@@ -355,7 +355,12 @@ void ESP32RMTController::showPixels()
         // -- This Take always succeeds immediately
         xSemaphoreTake(gTX_sem, portMAX_DELAY);
 
-        // -- First, fill all the available channels
+        // -- Make sure it's been at least 50us since last show
+        // this is very conservative if you have multiple channels,
+        // arguably there should be a wait on the startnext of each LED string
+        gWait.wait();
+
+        // -- First, fill all the available channels and start them
         int channel = 0;
         while ( (channel < FASTLED_RMT_MAX_CHANNELS) && (gNext < gNumControllers) ) {
 
@@ -364,9 +369,6 @@ void ESP32RMTController::showPixels()
             channel++;
         }
 
-        // -- Make sure it's been at least 50us since last show
-        gWait.wait();
-
         // -- Wait here while the data is sent. The interrupt handler
         //    will keep refilling the RMT buffers until it is all
         //    done; then it gives the semaphore back.