ESP32 Tone Generator (#20704)

Marlin/src/HAL/ESP32/HAL.h

@@ -90,6 +90,13 @@ extern uint16_t HAL_adc_result;
 // Public functions
 // ------------------------
 
+//
+// Tone
+//
+void toneInit();
+void tone(const pin_t _pin, const unsigned int frequency, const unsigned long duration=0);
+void noTone(const pin_t _pin);
+
 // clear reset reason
 void HAL_clear_reset_source();