然后再点击红色的部分Unused Pins,选择不需要使用的IO功能。选择As inputs,tri-stated。这个的含义写的很清楚,不需要我多讲了吧: Reserves all unused pins on the target device in one of three states: as inputs that are tri-stated, as outputs that drive ground, or as outputs that drive an unspecified signal.