writing out a .vcd file from spectre 

I'm working with a small (very small) SRAM circuit. I'm simulating the design using Spectre from within Cadence (icfb). I'm VERY frustrated with the waveform viewer that pops up when the simulation is done. I'd love to write out a .vcd file and use a viewer that undoubtedly will be more suitable for debug of a "digital" design. I plan on using GTKWave since it's free, though if i had access to nWave (part of Verdi, formaly Debussy) i'd do it in a heartbeat. Any help would be appreciated, even if it's to point me to another forum. 

By the way, a user (TAM1) has already kindly pointed me in the direction of the '-input mycmdfile.tcl' option for the simulator, then, add a couple of lines in that file instructing the simulator to dump the .vcd file for all levels. However, it seems that spectre doesn't like tcl commands (or at least the -input option). 

Hello Geezmaneti,

even if this Forum might not suitable for your request (I would try functional verification) I might be able to help you.

Did you looked into SimVision already? Here you're able to write out a vcd file as shown below:

From the menu choose export and change the database format.

Which version are you using? You say "icfb" - so that suggests to me that you're using the IC5141 release, which is very old (it was released over 8 years ago, and the graphing technology is considerably older than that).

The waveform tool has had some rather major re-implementation in the IC61 release, particularly in IC615 which has a new graph.

Even if you're using IC5141, you can still run "viva" from IC615 standalone and read the results from IC5141.

Regards,

Andrew.

The waveform viewer you are showing (in the background, behind your pop up window) is what i want. However, i get a very "analogish" style of waveform viewer. Keep in mind that i'm launching Spectre from Cadence and not standalone. I also have not come across a tool called SimVision.

 Nonetheless, i did find out that you can export the waveform from the calculator tool from within the waveform viewer (seems very convoluted). But i will have to figure out how to get that into a .vcd format (shouldn't be too hard).

 Thanks for the info. I will try posting to the functional verification forum as well.

 Mike 

Andrew, when i say icfb, that is what i type at the command prompt to bring up my Cadence design environment. This is what we were using at TI when i left 2.5 years ago. However, i was a "digital" designer in a mixed-signal group and i pretty much stayed out of Cadence except to import my design and do some debugg in our top-level simulation environment (which was managed from Cadence). I'm now back in school and this is for a project. Since i have digital design experience, i'm aware of much nicer waveform viewers (like the one in the image posted above) and various formats for those viewers... I am NOT very knowledgable about the Cadence environment. So i'm not sure about the ICxxx release numbers you speak of. I did click on the help button from within the Cadence log window and, aside a very long version number, it looks like the entire environment is called Virtuoso, though i thought that was the layout tool from within the environment.

I can also envoke the "analog environment" from the schematic window and i can choose Spectre as my simulator. I then setup some options, including my stimuli and my signals to output, then just click the green traffic light. Spectre will run and then a waveform viewer pops up with my signals. That waveform viewer might not even be part of Spectre for that matter. It might be a built in Cadence tool which makes sense due to the fact that i'm simulating this "digital" circuit in an "analog environment".

 I know this may not clear anything up, but i'm hoping (that was a lot of typing for me and reading for you).

 Thanks,

Mike 

Mike,

If you type getVersion(t) in the CIW, what does it output?

Andrew.

So you're using a recent(ish) hotfix of IC5141 (probably about 2 years old). You're either using AWD as the waveform tool (this is in the ADE Session->Options form), which is essentially 20-year old technology, or you could pick wavescan which is a Java-based graphing tool (only about 10 years old...).

As I said, one approach would be to run "viva" from IC615 from the command line and use the results browser in that to navigate to the result directory produced in ADE in IC5141.

You may be best logging a service request with customer support so we can talk you through all of this?

Regards,

Andrew.

Andrew,

Great info. Things are starting to fall in place. Yes, i'm using AWD (i was instructed to do so by the teaching assistant that taught the class on Cadence). However, I do have the option of wavescan, which i might play with if you think it'd be better.

Since i'm a student, i don't have access to customer support. Only the admin (my instructor) has access and he has respectfully declined to be the liason for me. So i'm stuck doing everything through the forum. I did try to sign up for an account that would give me access to customer support, but the account creation process asked for a key (or some sort of license number).

Lastly, I'm not sure i have access to any newer version of Cadence (IC615) so i'm not sure i can use viva. If i did have access, i would either have to search for the path as my "which icfb" simply returns /usr/bin/local/icfb (with no version discriminator in the path). I guess they could be running a version control tool, but i'm unfamiliar with the environment and would have to ask. I looked through my environment variables and didn't see anything that would point me to a version control hook, but that doesn't mean there aren't other ways of doing it.

 Mike