ESP8266 Community Forum

- Tue Jun 07, 2016 1:45 pm #48727 When I connect the module it makes an unpleasant change in the GPIO 2 pin. Although at the start the program, I initialize the state of the pin to LOW.
It is dangerous for my application. please someone knows how to avoid it.
thanks

- Wed Jun 08, 2016 1:25 am #48746 Hi, in the first 250mS (boot) you canot control the level of GPIO2. After that you can do with it as you wish. It's a pain if you want to use it with relays etc. The simlest way is to use a port expander IC (GPIO's 0 & 2 are fine for I2C) or an ESP with more GPIO's

Last edited by Barnabybear on Wed Jun 08, 2016 2:29 am, edited 3 times in total.

- Wed Jun 08, 2016 2:14 am #48750 I had the exact same problem, with a relay coming on momentarily before the software took over.

I tried a lot of passive component solutions to delay the drive to the relay transistor, without success.

Finally, used an 8 pin pic with a simple delay routine and stuck that between the ESP output and the relay drive; a bit of an overkill, but a single component solution that works flawlessly!