我想做一个简单的断言,检查两个值是否相等。是否有人可以解释行为时,我给你两个不同的值相同的变量当我们将2个值赋给同一个变量时会发生什么?
logic src_sig ;
logic dest_sig;
logic alt_sig;
assign a = src_sig;
assign a = alt_sig;
assign b = dest_sig;
我断言顺序是:
sequence check_seq(X,Y);
(X == Y);
endsequence
,就连最初的块是:
initial begin
#100 @ (posedge clk) begin
src_sig <= 1;
dest_sig <=1;
alt_sig <= 0;
end
#10 @ (posedge clk) begin
src_sig <=1;
dest_sig <=0;
alt_sig <= 0;
end
#10 @ (posedge clk) begin
src_sig <= 0;
dest_sig <= 0;
alt_sig <= 1;
end
#10 @ (posedge clk) begin
src_sig <= 0;
dest_sig <= 1;
alt_sig <= 1;
end
#30 $finish;
end
我期望第二个作业将覆盖第一个作业,或将其分配给src_sig
和alt_sig
。所以要么分别显示2个或4个。但我得到以下结果(3次犯)。
"testbench.sv", 31: test.check_assert: started at 103ns failed at 103ns
Offending '(a == b)'
"testbench.sv", 31: test.check_assert: started at 113ns failed at 113ns
Offending '(a == b)'
"testbench.sv", 31: test.check_assert: started at 133ns failed at 133ns
Offending '(a == b)'
请解释这里发生了什么?
编辑::完整代码
module test_gcc();
logic clk=0;
logic src_sig,dest_sig,alt_sig;
assign a = src_sig;
assign a = alt_sig;
assign b = dest_sig;
initial begin
clk = 0;
forever #1 clk=~clk;
end
sequence check_seq(X,Y);
(X == Y);
endsequence
property check_connection(M,N);
@(posedge clk)
($rose(M)||$rose(N)||$fell(M)||$fell(N)) |-> check_seq(M,N);
endproperty
check_assert : assert property (check_connection(a,b));
initial begin
#100 @ (posedge clk) begin
src_sig <= 1;
dest_sig <=1;
alt_sig <= 0;
end
#10 @ (posedge clk) begin
src_sig <=1;
dest_sig <=0;
alt_sig <= 0;
end
#10 @ (posedge clk) begin
src_sig <= 0;
dest_sig <= 0;
alt_sig <= 1;
end
#10 @ (posedge clk) begin
src_sig <= 0;
dest_sig <= 1;
alt_sig <= 1;
end
#30 $finish;
end
endmodule
我有一些想法,但没有[MCVE](https://stackoverflow.com/help/mcve)我不能再进一步了。请创建一个MCVE。 –
我已经粘贴了一个链接。如果您需要,我也可以发布整个代码。谢谢您的帮助。 – SShankar
您的问题在于您最初并未在您的问题中发布的代码。这就是为什么一个MCVE非常有价值。请编辑您的问题以包含您的所有代码。 –