Merge pull request #841 from arduino/jorgetrujilloroman/portentah7/ota-tutorial-addition

[PC-1116] Adding some information to the Portenta H7 over-the-air tutorial

Author: Jorgetrujilloroman

content/hardware/04.pro/boards/portenta-h7/tutorials/over-the-air-update/content.md

@@ -138,6 +138,50 @@ Convert your encoded file into `.ota` format
 
 You can use `OTA_Usage_Portenta.ino.PORTENTA_H7_M7` as a sketch name for facilitated identification of the file. After this, you will have the `.ota` file of the sketch that you will use with the OTA process. 
 
+### Installing Python 3 On Linux
+
+If you are using Linux, maybe you cannot run the **bin2ota.py** script. This may be because you need to install [Python 3](https://www.python.org/) and the necessary modules. To do it execute the next command on your **Linux terminal**: 
+
+```cpp 
+sudo apt install python-is-python3
+``````
+
+You will also need to install the **crccheck** module on python by following the next instructions:
+
+Installing pip on python:
+```cpp
+//Necessary to install python modules:
+sudo apt install python3-pip 
+```
+Installing the crccheck necessary module on python:
+
+```cpp
+//Necessary to run the script:
+pip install crccheck
+```
+Once you have done it, you should be able to run the bin2ota.py script successfully. 
+
+### Uploading OTA file to the net ###
+
+Now you can upload your .OTA file to an online reachable location, e.g. *OTA_Usage_Portenta.ino.PORTENTA_H7_M7.ota*  has been uploaded to: 
+
+http://downloads.arduino.cc/ota/OTA_Usage_Portenta.ino.PORTENTA_H7_M7.ota
+
+You can change the default file location on the code by modifying the next line on the ***"OTA_Qspi_Flash"** sketch or in the **"OTA_SD_Portenta"** sketch depending on which method are you going to follow:
+
+```cpp
+static char const OTA_FILE_LOCATION[] = "Introduce here your online OTA file location";
+```
+It is important to know that if your OTA file is uploaded to an HTTPS website you will need to modify the next line in the code:
+
+```cpp
+  int const ota_download = ota.download(OTA_FILE_LOCATION, true /* is_https */);
+```
+This line is in **line 87** for the **"OTA_Qspi_Flash"** sketch or in **line 88** on the **"OTA_SD_Portenta"** sketch.
+
+If you are going to use the example OTA file used in this tutorial you don't need to follow the steps in this section, just execute the sketch with the default file location.
+
+
 ***Now you have two options to choose, use QSPI or use an SD Card to storage your OTA file. You can use the left side index to jump to the option that you may need.***
 
 ### QSPI Storage Mode