ESP8266 Community Forum

- Mon Mar 21, 2016 9:21 am #43708 Fascinating post. I've been struggling with a Gizwits ESP-12F (running NodeMCU LUA) also not restarting properly from deep sleep.

Have now replaced the wire with a 470R resistor to see if it helps. Will try a bit lower if necessary but so far so good!

- Tue Mar 22, 2016 5:15 am #43770

@AdrianM, For the CH_PD, I would never rely on weak internal PullUps, especially that Espressif is saying the following since the beginning in the HardwareUserGuide :

The enable pin CH_EN (pin 7) can also serve as a reset pin. If voltage for CH_EN pin is low, the
chipset ESP8266EX will power off. Note that this pin cannot be dangled.

Hi martinayotte, that reference is to CHIP_EN which is certainly not to be dangled What I'm curious about is the 10K pull-up exclusively seen in Adafruit designs on GPIO16 aka CH_PD aka XPD_DCDC

I've been going by the Esspressif ESP8266EX Datashhet V4.4 which seems to map best with my ESP8266-12E parts, and it says:

3.1.1. General Purpose Input/Output Interface (GPIO) There are up to 17 GPIO pins. They can be assigned to various functions by the firmware. Each GPIO can be configured with internal pull-up (except XPD_DCDC, which is configured with internal pulldown)

SO if ever that pin were software configured for input, Adafruit boards would float that input mid-rail with no other connection to define it. Just trying to understand why they felt the need to do that

- Tue Mar 22, 2016 7:18 am #43781 CH_PD & GPIO16 are not the same pin.
CH_PD is a dedicated enable pin and cannot be configured as I/O (in newer datasheets it's called CHIP_EN/CHIP_PU).

- Tue Mar 22, 2016 7:30 am #43783

CH_PD & GPIO16 are not the same pin.
CH_PD is a dedicated enable pin and cannot be configured as I/O (in newer datasheets it's called CHIP_EN/CHIP_PU).

Hi lethe, thanks for putting me out of my misery