Making homemade pasta
There is not one correct answer to your question.  I've seen recipes with, and have used, both.  So, it depends on the type of pasta. A recipe for capunti (a hand rolled pasta from Puglia) that I enjoy, uses 1/2 semolina and 1/2 durum...  while an extruded pasta noodle might use all semolina. You might be guided by identifying the type of pasta, and its region of origin, to see what is typical. However, I would have to assume that when a recipe calls for semolina flour it generally means the course grind version.