Cadence Simulation Help Needed

[Digital-L0gik]

I am having a problem when simulating a circuit that my tran.tran.trn file is getting to be huge. The way I plot, is I go to output, to be plotted, select on schematic. I have a lot of inputs. I guess cadence is spitting out too much information into this file.

How can I reduce the size of this file? I saw a post on this earlier, I went to outputs save all and checked the selected box only. Can someone give me some clear instructions on how I should proceed?

Thanks.

 

[erikl]

... outputs save all and checked the selected box only. Can someone give me some clear instructions on how I should proceed?

AFAIK, with Outputs -> Save All ... all nodes of your schematic will be saved. To minimize the file size, use Outputs -> To Be Plotted -> Select On Schematic, and just select as many as you absolutely need. End your selection by [Esc] in the schematic view window.

 

[Digital-L0gik]

Thanks for responding. I encountered the disk space error only after I have been plotting only the points I click on the schematic. I ran out of space doing it that way. I googled the .trn file being big, and someone said to do go to outputs, save all, and check the box that says only selected. I am not sure if this applies to the way I have been simulating. Any other ideas out there? I appreciate it. I am not given much space to begin with. I have 50MB quota. It may just be that I need to get more.

 

[erikl]

... go to outputs, save all, and check the box that says only selected. I am not sure if this applies to the way I have been simulating.

Yes, should give the same result.

Any other ideas out there? I appreciate it. I am not given much space to begin with. I have 50MB quota. It may just be that I need to get more.

50MB actually is a bit low. Is this, possibly, the limit for your .trn file size?

As a short-term work-around you could perhaps split your simulation into several part-time runs, hoping to be able to restart the next part run from a previously saved oppoint file from the last sim run's end state.

Or: You could run the whole simulation once and save only the inputs, which (may be) shouldn't take so much file space (perhaps only a clock signal). Save (rename) the .trn file, then run the same analysis with only the output(s) saved, and try and combine the 2 .trn files (or perhaps tell the wave tool to first display from the first, then from the second .trn file).

Don't know if this will help you - I only successfully used the restart function for serial sim. runs. Good luck!

 

[oermens]

if using IC5x set the following variable, spectre will split the simulation files into 2gb chunks which can be handled easier by WaveScan:

setenv PSF_WRITE_CHUNK_MODE_ON true

Also if your hierarchy has several layers of depth but you are only concerned with the top few levels, set the save option to lvlpub and the value to however many layers from the top you want saved.

 

[Digital-L0gik]

Thanks for the help guys. I got a disk size increase but also employed some of the tips you used here. Thanks a lot!