ESP8266 Community Forum

- Wed Oct 10, 2018 3:19 am #78548 Hello,

I'm asking about these 3 GPIO's because they are used in bootstrapping.

Is there any limitations in using these pins for general input/output after startup condition has been passed?

For example: If I want to drive buzzer, drive LED or read button with these GPIO's.

Thanks,
Tipo

- Fri Oct 12, 2018 8:03 am #78595 With the information found in our Wiki, you should be able to find any limitations with the GPIO-pins of the ESP8266.

In short: don't assume that GPIO0, GPIO2 and GPIO15 are just like the other GPIO's.
As input, make sure they're properly pulled up or down and as output make sure anything connected (like a buzzer) influences the port at boot (at which time they act as input).

Assumption is the mother of all f*ckups. At least: that's what I'm assuming.