Transcript
Save Data from Cadence Simulation To Text File (ICFB 5) This is a brief tutorial to save data from Cadence simulations to a text file for parsing using your favorite program (MATLAB, NumPy, Excel, etc.). 1) Let's assume I have run a simulation in Cadence and have an output plot that looks something like this:
2) In the Plot window, go to “Tools” and select “Calculator”
3) The calculator should pop up. You can actually use the calculator to do operations on the data, but the syntax is similar to reverse Polish notation, so it can be hard to figure out the right sequence of selecting the plot and operation buttons. So, this will just show you how to select the plot. Make sure
there is nothing in the buffer area (you can press the “clear” button to empty it).
4) Click on the “Wave” button on the left side, go back to the plot window, then click on the actual plot (It helps to have the yellow box on it). The data from the plot should now be in the buffer of the calculator.
Since this is the drain current, you can see the value is /N0/D, which is the drain that was selected on transistor N0 in the schematic.
5) Click on the “printvs” button on the left side. It brings up a window like this:
If you click “OK” it will select all of the plot data. This pops ups the results window.
6) Since the Cadence default is to use units like “u” for micro-, “p” for pico-, etc., click on “Expressions → Display Options”
This brings up the Display Options dialog to change this.
Since many external programs don't understand “p” and “u” as units, go to “Format” and change it to “Engineering (exponent)”. This changes all of the “u”s, “p”s, etc. to “e-6” or “e-12”s. 7) Now, go to “Window → Print...”
This brings up the print dialog
Click on “File”, and input a file name. Remember, in UNIX, ~ means your home directory, where you typically have write permission, so it is a good place to save it. Now you can open it with any program that can read csv files (ie. MATLAB's importdata(), Python's csv module, or Excel). From here you can do whatever operations you'd like on the data and even plot it. 8) BONUS: Since the file resides on the VLSI server, you can use any SFTP client (ie. Filezilla) while on campus to copy the file off of the VLSI server.
