Simulation and Verification

[rhykie]

Hi,

I'm new to Xilinx ISE. I'm trying to make a simulation of a simple up/down counter using the ISim simulator in ISE 11.1. I have written the verilog code and the testbench, but then the problem is what to do next in order to "see" my simulations. When I try to simulate, the outputs waveforms stay constant regardless of having changed the values in the testbench. The clock values are written as z, and I dont know how to change them. I think the problem is I dont know how to set the clock frequency in the simulator. I tried to consult the manuals but I coulnt find help.

So I am asking for help on how to make simulations in Xilinx 11.1.

Cheers!

[awillen]

Well, you'll have to assign values to the clock signals (that's why they have the value z – the clock wire is not connected to anything). Open the "Language templates" in ISE, there are a couple of examples showing how to provide a clock stimulus.

Adrian