digitalWrite(LED_BUILTIN, LOW); // Turn the LED on (Note that LOW is the voltage level
}
void ledOff() {
digitalWrite(LED_BUILTIN, HIGH); // Turn the LED off by making the voltage HIGH
}
void ledToggle() {
digitalWrite(LED_BUILTIN, !digitalRead(LED_BUILTIN)); // Change the state of the LED
}
esp8266::polledTimeout::periodicFastUs halfPeriod(500000); //use fully qualified type and avoid importing all ::esp8266 namespace to the global namespace