Cadence Design Systems offers quite a few pieces of software that are used for designing computer hardware.  This document will talk about the most popular options used at UMD and how to access them.  Most of the available software packages from Cadence run on Linux but there are a few that run on Windows.

For issues running virtuoso or other programs using SSH, please see this article on using secure shell access.  If you are having issues with displaying graphics, please reference the secure shell access article.

Windows

• ORCAD/Allegro/SPB (sometimes referred to as PSPICE)
  • Available for student use in the virtual computer lab under Cadence 17_2 Design Entry CIS.
  • Available in some ECE computer labs as well.
• Datacenter Design
  • Available by request.

Linux

• Integrated Circuit
  • The main product used at UMD is Virtuoso.
  • Available in Glue/TerpConnect
    • ssh compute.ece.umd.edu (click here for more information)
    • module load cadenceIC
    • virtuoso
    • North Carolina State University CDK is available for some versions of Cadence as well.
• Support options
  • There are a dizzying array of software and support options.  If you need documentation, please contact eit-help@umd.edu.
  • If you ask for something like all of the documentation on IC 6.18, you will get a clarification response asking for specifics.  There are hundreds of documents that fall under this category.  You need to be specific.
  • The team that responds to eit-help@umd.edu is Engineering IT Operations and we do not have expertise in using the Cadence suite of software. We can point you to groups that do use different Cadence tools or we can provide specific documentation. We can also troubleshoot licensing issues.
• Common problems
  • If you see errors related to Virtuoso_Schematic_Editor_L, you may be experiencing a problem related to the first time you ran the schematic editor.  The first time you run it, it should prompt you to use the next available license (for  Virtuoso_Schematic_Editor_XL) and you should pick Always.  If you picked Never, you need to clean up this problem before you can move forward.
    • Look in ~/.cdsenv.  You probably see something line the line below.  Change "never" to "always", restart Virtuoso, and it should now work.  You can also simply remove .cdsenv (assuming there is nothing else in the file) or remove the single line below.  If you remove the line or the file, you should be prompted the next time you run the schematic editor.  If you change it to "always" and restart Virtuoso, it should now work.
      • license VSEL_UseNextLicense     string  "never"
  • If you see errors related to running out of processes, you may have been enrolled in a CS or ECE class that instructed you to add a process limitation in your profile to prevent issues.  This will cause problems with Cadence software products.
    • Go to your home space and look at your .cshrc.mine (most likely) and .bashrc.mine (less likely but good to check).
      • cd ~
      • vi (or emacs or whatever editor you use) .cshrc.mine
        • Look for ulimit or limit maxprox or limit process or something similar 
        • Add a comment by putting a "#" sign at the beginning of the line that has this in it.
      • exit
    • Log back in and your issue should be resolved
  • If you still have process related problems after doing the previous troubleshooting, you may have processes that are still running.
    • ps -ef | grep <username> (there are many ways to do this but ps by itself will only show your current session processes)
    • You can use kill or killall to get rid of unwanted processes that you own.
      • https://www.howtoforge.com/linux-killall-command/
  • Cadence lock files are not cleaned up due to crashing or an improper shutdown of the application you were using.
    • Make sure no Cadence software is running.
    • The command below should locate the lock files.  You then need to remove them manually using the "rm" command.
    • find ~ -name '*.cdslck'
    • rm <filename(s) returned by the command above>
  • Running out of storage space for your user.
    • You can check how much quota your user has available by running the command below.  If you have used all or nearly all of your space, you will likely have problems.  You need to clean up old files.  If you have issues, please contact the Engineering Service Desk team at eit-help@umd.edu.
    • fs lq ~<username>