学习verilog DHL问题笔记——Quartus常见错误(2页).doc

-我初学verilog语言，很多细节都没注意，按着自己的思想就写了，编译的时候才发现各种问题。这些都是我在学习中遇到的问题，还是很常见的。 1.Error (10028): Can't resolve multiple constant drivers for net 解析：不能在两个以上always内对同一变量赋值，这个细节一般看书看资料会看到，但是编程时，就是没想到。2.Error (10158): Verilog HDL Module Declaration error at clkseg.v(1): port "XXXX" is not declared as port解析：大意了，端口类型还没定义啊！3.Error (10110): variable "en" has mixed blocking and nonblocking Procedural Assignments - must be all blocking or all nonblocking assignments解析:en在程序中有时用非阻塞赋值，有时用阻塞赋值，这是禁止的。在初学的时候，可能分得不是很清楚，所以在检查时，一定要一步步观察慢慢来。4.Error (10161): Verilog HDL error at clkseg.v(36): object "count" is not declared解析：这个错误应该很明显啦，只要能读得懂。5.Error (10170): Verilog HDL syntax error at clkseg.v(37) near text "*"  expecting ""解析：意思应该也很简单，就是检查的时候要细心点。6.Error (10171): Verilog HDL syntax error at ir_ctrl.v(149) near end of file ;  expecting an identifier, or "endmodule", or a parallel statement解析：最后上了endmodule。一般编程的程序长了，到最后也就容易忘记。7.Error (10278): Verilog HDL Port Declaration error at ir_ctrl.v(11): input port "ir" cannot be declared with type "<a variable data type, e.g. reg>"解析：在Altra官网中就有该解释  官网上有很多东西值得我们发现学习。8.Error (10137): Verilog HDL Procedural Assignment error at test.v(24): object "check_9ms" on left-hand side of assignment must have a variable data type解析：在Altra官网中就有该解释 9.Error (10219): Verilog HDL Continuous Assignment error at clk_div.v(26): object "clkdiv_equ" on left-hand side of assignment must have a net type解析：看得懂英语就懂了。10.Error (10200): Verilog HDL Conditional Statement error at clk_div.v(22): cannot match operand(s) in the condition to the corresponding edges in the enclosing event control of the always construct解析：看看官网的解释11.Error (10231): Verilog HDL error at LCD1602.v(40): value cannot be assigned to input "lcd_en"解析:端口设置出错12.Error (10137): Verilog HDL Procedural Assignment error at LCD1602.v(49): object "lcd_rs" on left-hand side of assignment must have a variable data type解析：13.Error (10170): Verilog HDL syntax error at test_vga.v(57) near text "<"  expecting "<=", or "="即这里产生的错误。解析：一个空格，不小心分开了，而且有人喜欢把<=分开来写，这个在QUANRUS是不允许的呃。 14.Error: Application nios2-terminal on 127.0.0.1 is using the target device解析：这种情况出现在JTAG模式下，你在使用NIOS下的JTAG功能（比如利用BLASTER进行在线仿真），同时你又想下载*.sof文件（就是在JTAG模式下下载程序）。简单说就是你的JTAG已经被占用了。解决办法就是关闭你正在使用的JTAG功能，然后再下载*.sof文件。初学者经常会犯这样的错误，一定要注意。这里有-第 2 页-