ESP8266 Community Forum

- Fri Mar 11, 2016 8:42 am #42900 Hi, I've seen GPIO 0 has been damaged during flashing before now.
It generaly seems that people - Connect GPIO 0 to GND (button press) then connect RESET to GND (button press) - then relese RESET - then relese GPIO 0.
If you use the above order of events and GPIO 0 has been set as an output and is high at the time you conect GPIO 0 to GND the output wil be damaged (for some reason the damage leaves the pin always high when used as an output). Booting still works ok when the pin is an input (default) but you cant use it as an output.
I always - press RESET - press GPIO 0 - relese RESET - relese GPIO 0. Then this can't happen.

- Fri Mar 11, 2016 9:58 am #42904 Well, then this is likely what happened to me. Seems like I'll have to use the 12f module I have lying around then. Is that something that can happen to every pin or is it just the GPIO0 being very sensitive to shorts while being defined as an output? It would be nice to understand why exactly this happens so I can be more careful in the future. Thanks!

- Fri Mar 11, 2016 7:17 pm #42927 I usually connect GPIO0 to gnd thru a switched circuit resistor, then reset.....
circiut = V+ / LED / resistor / GPIO0 / resistor / switch / gnd...
Reset then Sw on LED lights bright/ press reset Led Dims
I use small leds and like 910R to led and 1500 to sw
circiut = V+ / LED / 910R / GPIO0 / 1500R / switch / gnd...
This working great for me [ dim led => flash mode (usually) bright led ( arduino loaded ok)

- Thu Jun 28, 2018 11:52 am #76707 I challenge anyone using an ESP8266-12F to prove GPIO0 can successfully be configured as an output. Loaded or open, all I get are oscillations (about 70kHz) when driving GPIO0 to LOW. Even GPIO15 works perfectly as an output. I tested this on several brand new 12F versions.

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