I have succesfully setup communication between Cerbo and MQTT relays via Node Red.
I have also created a flow for arduino using a Serial out.
Can that be used directly from the Cerbo’s USB ports or do they use a different protocol?
I have read the VE.Direct protocol page but I was wondering why not USB?
Thanks to the whole community
Well arduino atmega based usb-serial require special drivers. They aren’t standard USB-UART chips like the FT232 or CP210X. The reset fuction required for switching between the bootloaders programming/serial functions prevents a direct arduino connection over USB. You will always need a dedicated USB-serial adaptor chip as far as a know. If you provide that serial communication between Cerbo/arduino is quite simple.
Well, how do we explain that on my first attempt with Arduino nano the serial communication worked perfectly turning ON/OFF any digital pin?
Nothing special was done in Node-Red, just the following
It did not work with a a clone nor with a later genuine model though so I followed some instruction from the web using SSH, something like verifying the USB assignment, prioritising it etc.
Since then even the first perfectly working Arduino refused to function.