If you use Exceed from a PC you need to take care of
this extra issue.
The Cadence software has an annoying screen/refresh problem when run on a
PC via Exceed. You need to do the following in order to solve the problem:
Under Xconfig -> Performance.
this script modifies your environment (sets PATH and exports variables). To see your current environment type the following at the prompt:
mkdir cadence cd cadence mkdir tutorial cd tutorial mkdir HDL
For this tutorial you will need a few extra files, please download the following files in the HDL directory: accu.cmd accu.v accu_test.v
from: http://www.ee.virginia.edu/~mrs8n/soc/filesFrom the tutorial directory type:
nclaunch &The command nclaunch & starts NCSim in the background and you should get the NCLaunch startup window:
Please click on Multiple Step and you should now get the main NCLauch window:
The window has four areas:
Now we need to set the work directory and create a work library (to contain your circuits) so go to File -> Set Design Directory from the File menu of the Menu Bar. First set the design directory to the tutorial directory that you just created (this should be automatic if you started NCLaunch from the tutorial directory as described here):
then click on Create cds.lib File and click Save (you should only need to do this once when you run the tool for the first time)
and finally click OK to Include default libraries
Finally, making sure that worklib has appeared for Work Library click OK on the Set Design Directory pop-up window. Please notice that the Library Browser window (right side) of NCLaunch has become populated now.
There are 3 steps that we need to perform now (remember we chose multistep):
Close the text editor without modifying the file. Now compile both accu.v and accu_test.v in that order.
Caution! The order of compilation is important in case there are dependencies among the files. In the case the testbench is the "top" file and needs to be compiled last!
Make sure there are no errors in the Console Window (always keep an eye on that window for errors and warnings).
In order to elaborate first click on the + in front of the worklib on the Library Browser window in order to see it's contents:
Now select the top file under worklib (stimulus) then click on the Elaborate button in the Menu (immediately to the right of the VLOG button), or go to Tools -> Elaborator....
Finally we can simulate! Click on the + sign in front of the Snapshots library to expand its contents, then select worklib.stimulus:module and click on Simulate (next to the right of elaborate) or go to Tools -> Simulator.... This should launch the Simvision Design Browser and Console windows:
Click on stimulus on the left window, then on the Waveform button (the one that looks like a set of white digital waveforms on a black background, sixth from the right), this should open a new Waveform window. Now press on the Run button on the Design Browser window (first on the left, looks like a Play button on a CD player). This should now display the signal waveforms that validate correct functionality for the accumulator (increment by one for every clock cycle):
Congratulations, this is the end of the Simulation Tutorial.