错误：Error (176310): Can't place multiple pins assigned to pin location Pin_101 (IOPAD_X34_Y18_N21)

    Info (176311): Pin addr[8] is assigned to pin location Pin_101 (IOPAD_X34_Y18_N21)
    Info (176311): Pin ~ALTERA_nCEO~ is assigned to pin location Pin_101 (IOPAD_X34_Y18_N21)

原因：该引脚是一个多功能管脚（multiple pin），可以当普通IO来用也可以做nCEO,nCEO是默认功能，如果要用它做普通IO需要提前设置一下

解决办法： 在device  and pin options -dual——purpose pin ---把里面的nCEO设置为use as regular io 就可以了