Basic blinky example works with an ESP-12E but not with an ESP-12F

In ordrer to install all of esp-open-rtos toolchain and and blinky code example I've approximatively followed this protocol here at https://www.penninkhof.com/2015/03/esp8266-open-sdk/#comment-698

When flashing with esptool.py it works very well with an ESP-12E but not with the same board and an ESP-12F instead.

Additionnal infos:
I've the same problem by using eclipse.

(I used both of Ubuntu and Debian, it didn't change anything)

Start by reproducing the blinky example with the esp-open-rtos toolchain and esptool.py on both ESP-12E and ESP-12F, using the referenced installation protocol. Compare the flashing output and board behavior across Ubuntu or Debian; done means the example flashes and runs on ESP-12F as it does on ESP-12E.

Written by the indexing model from the issue text.