At any one time at least some of the tools will be grayed out.

Assemble - Assemble the currently entered code. Assembly will stop at the first error and the assembler will indicate the line and probable problem.

Debug - Toggles simulator into debug/run mode. Opens or allows user to open windows that allows the user to examine main memory, stack memory, cpu register contents, and the I/O window. Activates several of the following tool buttoons.

Run - runs the current program to finish at normal speed.

Step Over - runs only current line of program starting at beginning. If sub-routine encounted, subroutine runs to to return before execution stops. Step Into - runs only current line of program starting at beginning. If sub-routine encounted, enters subroutine and execution stops.

Run To - runs from beginning of program or last place stopped to the current location of the cursor in the source code. Animate - runs the program at a reduced speed, drawing an arrow to the left of the source code to indicate current line being executed.

Restart - terminates the current run of the program and restarts at beginning.

Toggle Breakpoint - sets or clears a breakpoint at the current line under the cursor. When the run command executed, execution stops at breakpoint. Clicking on run again, will restart execution at the breakpoint line.

Stop - stops the execution of the currently running program.