Error (10028): Can't resolve multiple constant drivers for net "out2" at shiyan.v(14)解决办法

//Error（10028）：Can‘t resolve multiple constant drivers for net “ ” at **.v

//两个进程里都有同一个条件判断的话，会产生并行信号冲突的问题。

//同一个信号不允许在多个进程中赋值，否则则为多驱动。

//进程的并行性决定了多进程不同能对同一个对象进行赋值。

 1 module test(c1,c2,out1,out2);
 2
 3 input c1,c2;
 4 output out1,out2;
 5
 6 reg out1,out2;
 7
 8 always @(posedge c1)
 9     begin
10         out1<=0;
11         out2<=0;
12     end
13
14 [email protected](posedge c2)
15     begin
16         out1<=0;
17         out2<=1;
18     end
19
20 endmodule                    

上面的代码在quartusII里面就会出现题目的错误提示，器原因就是在两个always语句里面都对out1,out2信号赋值了，而两个always是并行快，所以提示出现多重驱动的情况。。。

解决办法：

将两个always合并为一个

 1 module shiyan(c1,c2,out1,out2);
 2 input c1,c2;
 3 output out1,out2;
 4
 5 reg out1,out2;
 6
 7 always @(posedge c1 or posedge c2)
 8     if(c1==1)
 9         begin
10             out1<=0;
11             out2<=0;
12         end
13
14    else
15         begin
16             out1<=0;
17             out2<=1;
18         end
19 endmodule

摘自网络：

http://blog.sina.com.cn/s/blog_5c5263cf0100qd2q.html

http://www.cnblogs.com/woshitianma/archive/2013/01/12/2858051.html

Error (10028): Can't resolve multiple constant drivers for net "out2" at shiyan.v(14)解决办法