MaxBlitz: How to restore the ESP8266 AT command firmware

If you need to restore the ESP8266 firmware, follow the instructions below:

1) Connect the FTDI adapter, an external power source, and set the jumpers as below:

2) Upload an "empty" Arduino sketch to be sure that all the ports are not in use. Note the FTDI COM port in the IDE bottom right corner:

3) Close the Arduino IDE

4) Download the ESP flasher software:
    https://drive.google.com/file/d/0B7n8Axhg7tChaHlLSENjWE5XRGM/view

5) Unzip files in a folder (e.g. C:\ESP8266)

6) Run "esp8266_flasher.exe" program

7) Set the FTDI COM port, as shown in step 2:

8) Click the "Bin" button and select the file "ai-thinker-0.9.5.2-9600.bin":

9) Click the "Download" button:

10) Wait while the firmware is transferred to the ESP-01:

11) Close the window when download is done:

12) You can test the firmware typing "AT" in the serial monitor of Arduino IDE:

   If "OK" appears, the AT command firmware is properly installed:

13) To check the firmware version, type "AT+GMR" and click "Send" button:

14) Set jumpers to the default position: