Usage of verilog compiler directive in TCL

 I don't think there's a way to do this directly. Normally you would use the TCL command "describe" to get information on a simulation object (net, module, class etc).However, a `define is a compiler macro, and in Verilog isused as a simple text substitution.
Thus by the time the simulator ges to execute the code, it doesn't really have any idea that the macro even exists, it will have been substituted for some text long before.

I am loathe to recommend doing any kind of etstbench in TCL when there are so many better ways to do it.
Still, if you really must use TCL, then I would recommend that you extend your Verilog testbench, and copy the important `define values into some parameters or other such object that can be used with the describe command.

... that's the way I'm using, define parameters in Verilog to drive the simulation, so the question is: can I recall these parameters in TCL?

about the usage of TCL: i like it because you can change everything you want with no elaborate time, you can't do so in Verilog of course!

I think we're confusing each other with the terminology! :-)

You initially asked about `defines, such as:
    `define BUS_WIDTH 32
These cannot (as far as I know) be seen from TCL.

 When I said parameters, I specifically meant Verilog parameters, such as:
  module foo (...);
    parameter BUS_WIDTH = `BUS_WIDTH;

These ARE accesible from TCL, so you can do things like:
  ncsim> describe tb.dut.BUS_WIDTH
And ncsim will tell you the value as a text string that you can manipulate in TCL.

Does that help clarify things?

Yes, you're right we've made some confusion, it's my mistake!

Ok, I'll try with describe command. Thanks

Hi StephenH,

I tried using following command in ncsim:
ncsim> describe tb.dut.BUS_WIDTH

And I am getting following result:
tb.dut.BUS_WIDTH...parameter logic [31:0] = 32'h00000001

I want to assign this value to tcl variable. Do you know how to assign it?
I have tried following:

set prm_bus tb.dut.BUS_WIDTH

But when I print the value using
puts $prm_bus
It prints tb.dut.BUS_WIDTH, not 1.