Simulation/Replay View

The Simulation View is shown after the Simulation button in the Tool Bar has been pressed and the Simulation preference page confirmed. At the top of the view there is a label showing the selected simulation type (Random Simulation, Guided Simulation, or Interactive Simulation) including the Promela model file name and four Simulation/Replay buttons: Run, Stop, Message Step, and Single Step. The simulation type can be changed by clicking the View Menu (a small downward pointing arrow in the top right corner of the Simulation View) and selecting the new simulation type from the drop-down menu that appears.

By clicking the Run button, the simulation starts and continues without stopping till the end or till the click on the Stop button. MSCs are being refreshed periodically each time the MSC refresh interval expires as given on the MSC Viewer preference page. The default and minimal value of the MSC refresh interval are 5 and 1 millisecond, respectively. During the simulation run the replay buttons Message Step and Single Step are being disabled. They become enabled again when the simulation ends or is stopped. By clicking the Single Step button, a user can replay the simulation run step by step through Promela model statements. On the other side, by clicking the Message Step button, MSC is being drawn message by message (if any message is sent and received in the model at all) and process by process (each time a new process has been created). Message by message and step by step simulation replay can be combined. For example, by successive clicking the Message Step button a user could come to the interesting part of the simulation trace, then replay it in detail by clicking the Single Step button and finally use the Message Step button again. Not only the simulation run, but also the replay can be stopped with a click on the Stop button.

Several Simulation View options to adapt the display of MSCs are available below the simulation buttons. The user can do the following: For the first four options, a hint about the input command syntax which has to be typed into the corresponding text field together with an example of use is displayed if you place the cursor above that text field.

During the simulation run or replay the variable values and queue contents values are updated in two separate tables at the bottom of the Simulation View. The current simulation step number is shown at the top of the tables.