- Simulation Part
- At the Unix prompt:
vhdlsim tb
- Trace some signals. In the simulator, type
trace /tb/A
. This will bring up the simulator window and trace the signalA
in the entitytb
.The first time you do this, Synopsys needs to go through an annoying "Font enumeration" process. This only happens the first time you use it on a particular system.
Now, trace the
B
andC
signals by typingtrace /tb/B
trace /tb/C - Simulate. In the simulator, type
run 1000
. This runs the simulation, tracing the indicated signals, for 1000 ns. - The Waveform Viewer:
- The zoom buttons:
- Create a marker:
If you zoom in enough, you will see that the
C
signal changes 4 ns after the input signals, because of the 4 ns propogation delay in the model (2 ns from each gate). - Leave the simulator. Type
quit
.
- At the Unix prompt:
- Automate the simulator startup.
At unix prompt:
emacs sim.scr &
Uncomment the lines:
trace /tb/A
trace /tb/B
trace /tb/Cand
run 1000
Next time you start/restart the simulator, it will automatically trace these signals and run for 1000 ns.
- Gracefully Exit
- First, exit the simulator by typing
quit
(if you're still there). - You can safely delete everything in the
work/
directory, it's just taking up disk quota and you can re-analyse if you need to. The commandrm -rf work/*
removes everything in the directory. - Check
ps -u userid
If there are still any Synopsys-related processes running, you should kill them:
kill PID
- First, exit the simulator by typing