Most blocks have parameters and initial conditions associated with them that let you set attributes that are specific to the block. You define and change parameters through a block Properties dialog. If you display a Properties dialog while the simulation is running, the simulation halts. After you close the dialog, the simulation is immediately updated to reflect all changes you made to block parameter values.
To access a block Properties dialog
•Right-click the block, or choose Edit > Block Properties and click the block.
Note: Right-clicking a block is a shortcut for accessing the Properties dialog for most blocks. For button, compound, and userFunction blocks, press CTRL+ right-click to access their Properties dialogs.