To use the Stimulus debugger in MPLAB, first start the simulator by selecting Debugger>Select Tool>MPLAB SIM from the menu. Bring up the stimulus window by selecting Debugger>Stimulus>New Workbook from the menu. Next, click on the “Asynch” tab of the stimulus window and choose to run, step, or animate the application in the simulator. Then click the “Fire” stimulus buttons (“>”) to cause an asynchronous stimulus to occur. Initially, the arrow “>” symbol does not appear on a new row. It will appear as soon as all the elements of the stimulus on that row are defined and the current cell is deselected. Before firing another stimulus, repeat step 5 by choosing run, step, or animate from the toolbar.