​ Hi, I wrote​ before​ about why it's very probable that David Vinci knew about the Americas and that they are seperate from Asia​,​ over​ here​.

See also the other answer in that thread about connections between him,​ his patrons the​ the Medicis, and Amerigo Vespucci.

Hopefully others can add more specifically on Da Vinci's writings, hope ​this helps already!​