编译通过,仿真报错如下不知为何?大神们,帮我快看看,万分感谢!
Error: Zero-time oscillation in node "|address|Add1~0" at time 0.0 ns. Check the design or vector source file for combinational loop.
代码如下:
module address(dir,clk,div,addr);
input clk,dir;
input[8:0] div;
output[8:0] addr;
reg[1:0] count_addr;
reg[48:0] count;
reg fenpin_clk;
reg[8:0] addr;
always @(negedge clk)
begin
count=count+1;
if(count==500000) //fenpin 20ms
begin
count=0;
fenpin_clk=~fenpin_clk;
end
end
always @(negedge clk )
begin
if(dir==0)
begin
count_addr=count_addr+1;
if(count_addr>=2)
count_addr=0;
end
end
always @(count_addr)
begin
case(count_addr)
0:addr=addr+div;
1:addr=addr-div;
default:addr=addr+div;
endcase
end
endmodule |