Help:How to assign the ports?

Thanks ,Brand.

After reading your thread, i understand something deeply, especially time constrain. Also your recommendation very good. I don't know them before, thanks very much again.

Now i have a new problem needed to address. That is how to constrain and set the Quartus when the classic timing analyzer and the time-quest analyzer.

The device i use is Max EPM1270F256c5, when i use classic one, i set the time-driven compilation as all path; i don't constrain the Tst,Tpd,Tco,and Th; the ports i set in assignment editor have many choose,etc. "Not a clock" "clock setting" "Auto global clock" and so on, i only know some of them,still many constrains are unknown, what material can i see?

When i use The time-quest one, i just constrain the ports in assignment editor, is there any constrains i still need to?

The time constrain really bother me, i know it not easy to do for a beginner like me. Maybe my question is naive ,but i want to make it well done!

Thanks very much ,everyone!