ESP8266 Community Forum

Hope this is not a FAQ.

When doing everything event driven, you still need loop() to make the linker happy. Is there a negative impact of an empty loop() function in terms of cpu usage or power consumptions? Are there any alternatives?

In theory no (you could test it fairly easily), but the Wi-Fi-core needs air to breath, so you should build in a yield() inside the loop I guess.

I'm not sure, but IMHO yield() is probably not required inside an empty loop() function as esp_schedule() is called within loop_wrapper() in core_esp8266_main.cpp (see also https://arduino-esp8266.readthedocs.io/ ... and-delays).

So I think an empty loop() should be fine