Digital is a simple simulator for digital circuits. You can place the circuit in a simple panel and connect the elements by wires. If your circuit is complete you can turn it on and interact with it.

There are two modes of wow to run the circuit:

At first there is the normal or full step mode started by clicking . In most cases this mode is suitable. If you modify the running circuit by turning on an input or entering an input value, this modification is propagated along all elements in the circuit. What you end up with is the state of the circuit after all changes are calculated and this state is shown in the main panel. Now you can do an other modification and the calculation starts again. In short: All calculations are done until the circuit became stable again. But sometimes this will never happen: Sometimes the circuit starts to oscillate. In this case an error message is shown. To find out whats going on in this case you can use the single gate mode.
The single gate mode is started by clicking . In the single gate mode the elements are highlighted which had a change at on of their inputs. But the reaction on this change is not calculated, the outputs are not updated. To calculate the reaction on the modification you have to click the single step button . Clicking this button the outputs of all highlighted elements are updated. Now maybe some other gates have changes on their inputs. But again the outputs are not updated until the step button is clicked. So you can follow the propagation of an input modification gate by gate.

In the examples folder you will find a lot of examples of different combinatorial and sequential circuits. Play around with them to become familiar with how Digital works.

How do I get set up?

maven is used as a build system
So you can simply run mvn install to build Digital
With mvn site you get a checkstyle, a findbugs and a cobertura code coverage report

Contribution guidelines

If you want to contribute send me just a pull request
Don't introduce new checkstyle errors
Don't introduce new findbugs errors
Try to keep the test coverage high. The target is 80% test coverage at all non GUI components.
Until now there are no GUI tests. Try to keep the amount of untested GUI code low.