I'm pretty happy getting my ESP connected to WiFi within approx 1 sec if I use static IP and deep sleep. Power supply remains connected, and I reset ESP with an pushbutton to wake him up to do some work.
To reduce power consumption even further, I now use an MOSFET to switch off the ESP completely. If i start the ESP after such power off, connection time increases significantly up to several seconds.
Somewhere I read about some WiFi connection credentials saved in Watchdog / RTC RAM. These credentials (must be more than SSID and PW) are told to be responsible for that fast connect.
How can i sped up my connection time after power on in the same way? Is it possible to save these connection details in FLASH?
Thank you in advance!