In looking at the ASCII pin-outs for a package (e.g., xc7z010clg400), why am I seeing Vcco pins present for a bank that does not exist (e.g., bank 13 does not exist, but Vcco pins do)?
Is this an error?
This is not an error. The Vcco pins are present to bring awareness to the fact that these banks are availble in other density parts in the same package. This is important for a user who may migrate to larger or smaller device densities within the same package and family.
The relevant Packaging User Guide that points to the ASCII pin-out files will actually have a note describing that these pins are intended for migration with suggestions on how to handle these pins.