I have trouble compiling the original sketch but I have a working copy in an ESP8266. Is it possible to read back the firmware from that esp8266 (NodeMcu) and copy onto another esp8266? I read that it is possible to use the esptool.py to do that but don’t know how?
I think this page explains exactly what you want to do:
I hope this helps.
Thank you. Can this commands be executed from a Windows PC? It seems to me that these commands are run from a Linux sysem.