Using LCD Class Object as static member

[Whandall]

I don't see the benefit to tie together one special LCD and a fixed 115200 baud rate,
maybe you could enlighten me.

@Flub

    static LCD lcd(OLED_V2, A13, A12, A14, A8, A9, A10, A11);

A static function that returns a LCD with syntax errors in the parameter definition. Strange.

@Flub

    static PCI* pInstance; // Static variable holding the pointer to the only instance of this 

A pointer to what? There is no dynamic part that could have a different address.
What makes that different from this (in class context)?

@Flub

PCI& PCI::Instance(){
  if (PCI::pInstance == nullptr)
    PCI::pInstance = new PCI();
  return *PCI::pInstance;
}

That is strange for the same reasons.
Using a hidden constructor and pointer access to a static only object is senseless,
because any member can always be accessed via the <class>::<attribute> syntax.

So, this whole project seems to be rather strange and superfluous, besides syntactically wrong.
You have no embedded LCD object.

I see static only objects as a kind of automatic singleton, all users use the same object.