TESTING YOUR DESIGN

When you think you've got your design working properly, press the "Run Test" button in the bottom right corner of the Workbench. This will automatically switch to the Test setup and start a waveform generator/recorder pre-programmed with a test sequence.

You will see the input waveforms being fed to the chip and the output waveforms that it is producing. The expected output waveforms are shown in grey for comparison.

Note that it doesn't matter if your output waveforms aren't perfectly square or they wiggle up and down a bit, as long as they have the right logic levels at the right times. Also, there is some tolerance allowed in the timing, so your actual outputs can rise and fall a little later than the expected waveforms and still be considered correct.

When the test is finished, you will be given a summary of the results. If the design passes, you will be allowed to proceed to the next design task.

Design Statistics

As well as the correctness score, the test results also include some statistics:

* Supply Current - Average current drawn from the power supply
* Propagation Delay - Average time between expected and actual output changes
* Silicon Area - Area of bounding rectangle around silicon (metal is ignored). This corresponds roughly to the size of the silicon die we will need when we manufacture the chip.

These statistics don't affect whether your design passes or not, but lower numbers here mean a better design.