Hello,
The project is complete and working well.
I attach photos to feed the album of the site.

Sincerely.

Hello Jeelet,

Thank you for the encouragements.
Your advice to save (protect) the Oled screen is also welcome, thank you.
My code expects it, the text is mini and moves every 3 seconds. Press a key and the menu returns.

Cordially.

Hello,
The project is complete and working well.
I attach photos to feed the album of the site.

Sincerely.

Hello,
Thanks to @JeeLee for answering me.
This is the only and first MySensors network that I am installing. There is no RADIO, only the Gateway_Serial USB link.
This morning I changed the Adafruit_SSD1306 & GFX library of the Oled to that of Tiny4kOLED and for the moment everything seems to be working correctly.
Here is my setup:

And the beginning of the code:

If I run into any problems again, I'll come back here.
Cordially.

Hello,
First of all, I apologize for my language, which comes from the translation.

I discover MySensors, and I see that great work has been done to develop this system, congratulations!

I use Domoticz with a PI3B, and I wanted to install a 4x4 keyboard with a small Oled screen. A way to be able to stop the alarm if the Wifi or internet is no longer present, yes it happens...
So I discover MySensors, I say to myself why try?
So I get a Nano+Keypad+Oled I2C.
The Nano is the Gataway and connected via USB to >RPI 3B.
During my PC tests connected to the Nano, my program works very well.
On the other hand, when I plug it into Domoticz, the Nano bugs quite quickly and Domoticz drops it.
My question: is it possible to make the whole thing work??? There seems to be a conflict with the serial port and I2C.
What do you think?
Thank you in advance for your replies.
A+