前言

在玩uart实验的时候，发现有这样的错误，之前一直以为是自己的代码设计有问题。今日在这里找到了答案，记录下：
Error (176310): Can’t place multiple pins assigned to pin location Pin_101 (IOPAD_X34_Y18_N21)

Error (176310): Can't place multiple pins assigned to pin location Pin_101 (IOPAD_X34_Y18_N21)
	Info (176311): Pin rs232_tx 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)
Info (171121): Fitter preparation operations ending: elapsed time is 00:00:00
Error (171000): Can't fit design in device
Error: Quartus II 64-Bit Fitter was unsuccessful. 2 errors, 0 warnings
	Error: Peak virtual memory: 4888 megabytes
	Error: Processing ended: Thu Nov 26 15:18:47 2020
	Error: Elapsed time: 00:00:01
	Error: Total CPU time (on all processors): 00:00:01
Error (293001): Quartus II Full Compilation was unsuccessful. 4 errors, 5 warnings

解决方法

打开quartusII的assignment，找到device，打开下面的界面，修改即可得到。