Deep sleep for ESP8266-DEV

[mhaas]

Hello all,

I am trying to use deep sleep with the esp8266-dev board. The board is powered directly from 3 1.2V eneloop batteries in series. I have connected RSTB to GPIO16 and loaded a simple sketch:

Code Select Expand


void setup() {
  Serial.begin(74880);
  Serial.println("FOO");
  // put your setup code here, to run once:
  delay(100);

}

void loop() {
  // put your main code here, to run repeatedly:
  Serial.println("Woke up - going back to sleep!");
  ESP.deepSleep(20  * 1000 * 1000);
  delay(100);
}

With my jumper connected between RSTB and GPIO16, the ESP keeps rebooting in an endless tight loop. Without the jumper, the code runs once and the ESP never wakes up again (as expected).

I have compared the schematics to the NodeMCU 1.0 and tried adding a pull-up to GPIO16 to not avail - I'm still getting the same result.

Besides the ESP8266 itself and the connection from RSTB to GPIO16, I also have a DHT22 connected to GPIO13.


So, my questions would be:

• Is deep sleep working in general?
• What setups have people used?
• What am I doing wrong?

Best regards

Michael

[mhaas]

Hrm, I just noticed the reboots go away if I touch my multimeter probe or my finger to one of the pins. I guess there might be a bad connection somewhere.

edit: I just removed the jumper and hardwired RSTB to GPIO16 - still getting bootloops. Any ideas would be appreciated!

[mhaas]

Long story short: if your esp8266 keeps resetting/rebooting when waking up from deep sleep, make sure that your input voltage is not too high. Three AA batteries (rechargeable) have more than their nominal 3.6V when fully charged. With some slightly discharged batteries, deep sleep works just by connecting gpio16 to rstb.

I think I will add a diode or perhaps a very efficient LDO..