Cool Things You Can Do With DVE – Part 3
Posted by Yaron Ilani on April 13th, 2011
Yaron Ilani, Apps. Consultant, Synopsys
If you missed part 1 or part 2 of this series don’t worry, you can go on reading and catch up with the previous parts later on. Today I’m going to show you a small, yet very powerful feature in DVE that you may not be aware of.
Remember the last time you had to count clock cycles in the waveform window? Sometimes this is a quick way to verify that an internal counter behaves correctly or that a signal goes up just at the right clock edge. Remember how frustrating it is when you lose count for some reason and have to start over? Remember how you’re never 100% sure about the result even if you calculated the time difference between the left and right cursors and divided by the clock period? If your answer was yes to any of those questions then you’re going to love the Grid feature. What Grid simply does, as its name suggests, is draw a grid on top of the waveform. Here’s what it looks like:
If you click on the Grid button (in the red circle) the Grid will show up as dotted lines. As you can see, the Grid can count clock cycles for you. You can set it up to count falling edges, rising edges or any edge. You can also set the range either by entering the start time and end time, or simply by placing the cursors at the desired points and clicking on the “Get Time From C1/C2” button in the Grid Properties window:
The Grid Properties window lets you have even more control over the grid. For example – you can set its cycle time to a custom value. This could be very useful if you want to be able to visually inspect drifting clocks or duty-cycle issues, etc.
In short, the Grid is one of those little things that make a big difference when it comes to efficient debugging and you should definitely become familiar with it. If you ever have to count clock cycles again, remember that you no longer have to do this manually. You don’t even have to make any calculations. Simply launch the Grid and voila!