Debugging you design with Simvision

Simvision is a unified graphical debugging environment for Cadence simulators. It can be used for viewing waveform, watching source code, and tracing driver or load.
In order to debugging design with Simvision, firstly we need dump waveform in SHM format, and then use Simvision to analyze waveform and design.

1. Dump waveform in SHM format with NC simulator

In order to dump waveform in SHM format with NC simulator, you should prepare a .tcl file, and use it as input when do ncsim, that is: ncsim –input xx.tcl …………….

Here is an example of .tcl file:
run 100000ns
database -open waves -into waves.shm –default -event //create database waves.shm
probe -create top -depth to_cell -tasks -functions -all -database waves –name proaa //create probe proaa, which specify download all signals(except memories) in scope top into waves.shm
run 50000ns
probe –disable proaa //disable probe proaa, stop dump waveform
run 200000ns
exit
In above example (assume that above .tcl file named ncsim.tcl), ncsim.tcl specify dumping waveform from 100000ns to 150000ns, and dumping all signals (except memories) in scope top into waves.shm.

For more detailed information about these command, please execute /cad/ldv5.4s011/tools.lnx86/bin/cdsdoc, open NC-Verilog, then open NC-Verilog simulator help, and then open 12.using TCL command – line interface. Or you can refer to /logic/judylu/simulator_commands.html#1042397.

2. Debugging design with SHM and NC snapshot

After simulation finish, you can debug design with Simvision.
If you have specify dump waveform, you will find there is a directory named *.shm (such as waves.shm). In this directory, there are 2 files, the one is *.trn, the other is *.dsn. The former stores signal values, and the latter stores other design information.

First start Simvision, and then open database such as waves.shm/waves.trn. Then you can view the waveform dumped. If you want to view source code or you want to do trace, Simvision will load the snapshot automatically. So if you want to view source code or you want to do trace, you can not delete you library.

You can find Simvision user guide at cdsdoc: NC-Verilog: Simvision User Guide.