ESP8266 Community Forum

- Sat Jan 16, 2016 7:40 am #38956 Hi guys,

I'm working with ESP12 and an RGB led (common cathode) wired as follows:

ESP GPIO12 -----> R
ESP GPIO13 -----> G
ESP GPIO14 -----> B
(Cathode pin connected to GND)

I noticed that during the deep sleep the LED is slightly turned on and, after the deep sleep (when the ESP starts again), it makes a fast blink.
The strange is that before calling ESP.deepSleep the led is completely turned off and also after it starts again I turn off the led as first.

What can I do to be sure that during deep sleep the LED is completely turned off and then it doesn't make a blink?
Can you help me?

Tell me if you need further information

Thanks
Big

- Sat Jan 16, 2016 8:04 am #38957 Try disable internal PullUp resistors before DeepSleep.

- Sat Jan 16, 2016 9:20 am #38962 I doubt that internal pullups are the source of the problem, especially that those are so "weak" (about 100k).
There must be some code that place those GPIOs as output with HIGH state.

- Sat Jan 16, 2016 10:02 am #38965 What little I tested deep-sleep it seemed to me that all pins go to their default state, but the current you can draw through the pins during deep-sleep is some fraction of the normal. I could, of course, be wrong about this, but that'd explain why your led is dimly lit during deep-sleep.

I haven't found anything yet to confirm this, though.