Thank you very much for your reply, in the meantime I wanted to test the display with the 5V power supply via the printer motherboard and it works fine. it did not emit flickering or other artifacts. we have already started to create our GUI, I have some doubts about programming in HEX code which I have never done, but step by step we will explore this field too.
PS: a problem with the display has arisen in the meantime, but I have opened a new thread so as not to mess with this one