I have Icarus Verilog installed on macos, but when I run it in the terminal to get a .vcd file, it always give me these messages:
ben@Bens-macbook ~ % iverilog -o khanh.vvp khanh_tb.v
khanh_tb.v: No such file or directory
No top level modules, and no -s option.
Can anyone help me with this problem?
Those error messages mean that the input file (khanh_tb.v) is not in your current directory.
Either change your current directory to the one where the file is, or run iverilog and specify the path to the .v file:
iverilog -o khanh.vvp path/to/khanh_tb.v
path/to/ is just an example; you should change it to the directory where the file resides.