Difference Between NC Verilog ,VCS and Modelsim

vcs verilog

Hai friends
Can any one tell me the difference between those simulator tools and which level they use those tools.If there is any document send to my email id

Email ID :adsenthil@rediffmail.com

modelsim vcs

There isn't much of a difference between these three. I think biggest differences are that ModelSim runs on Window as well as Unix/Linux. NC might be the fastest. ModelSim might be be cycle-based simulator only. You might the biggest differences in SystemC/System Verilog implementation. But all three are good mixed language simulators. Modelsim has good TCL support and integration but might be the slowest. I'd say ModelSim has the largest marketshare.

verilog vcs

diffrence in price, platform support, taste ...

vcs modelsim

They are different EDA vendor's product.

vcs vs modelsim

These are the worst answers I have ever seen.

There are big differences between the simulators.

1. The performance of the simulators change with all of the new languages added - so it is kind of hard to say which is fastest.

2. Some of the simulators are much more friendly to verification environments than others. For instance, Mentors ModelSim is much easier to use than Cadence's NC Sim for a couple of reasons.

- Globals - allow you to override parameters at run-time (have a long startup counter??)
- Dynamic Linking - each module is linked at run time.

This isn't a comprehensive statement though - there are other things about Mentor's ModelSim that really stink. For instance, if you like using the GUI of a simulator - ModelSim's has a nasty habit of crashing if you do too much and of being a memory hog. They may have fixed some of this, but I had this experience for some time.

Now VCS - when I used it, was the fastest and had the best SVA support.

3. Support for Advanced Languges - VCS had a head start on Mentor and Cadence on System Verilog (which seems to be the big winner in ABV). Cadence and Mentor have good PSL support - but it seems that SVA is winning the market. Additionally, Synopsys has the VMM (pre-canned SV stuff for your TB, and assertions). Cadence and Mentor have joined together to counter the VMM, and it is called OVM. I still haven't seen it yet.

Anyway, price is usually the leading factor in determining which simulator you're going to use because the simulator is something that is usually thrown into a deal - and not the main purchase.

Re: vcs vs modelsim

This is the main difference.
ModelSim is implemented based on Interpretters, VCS and NCSIM are implemented based on Compilers.