Today I solved one of my “Auto-reset” like problem for ESP8266 which had some erratic comportment depending on ESP module used. Sometimes it was working all time and some other never. Investigation was planned, I really don’t had time for this but I like to understand what’s going on, and why ! I also wanted to share this with you so will be able to discuss on it.

I’m already hearing people saying, “why getting worried with this since now OTA (Wifi update) is working” ? Correct, but having classic FTDI serial connection can sometimes get you out of troubles, you need it one day or another in case of problem and also for the 1st flash time setting.

Source: ESP8266 Reset and CH_PD pins for FTDI auto reset – Charles’s Blog