THE MAGAZINE FOR COMPUTER APPLICATIONS
Circuit Cellar Online offers articles illustrating creative solutions
and unique applications through complete projects, practical
tutorials, and useful design techniques.

AN HC11 FILE MANAGER

Part 2ýAll of the Details
by Walter Krawec

Introduction ý Format() ý Install() ý Directory() ý Run() ý Menu() ý Saving Memory ý Interfacing to the File Manager ý Two Sample Programs ý Conclusion ý Sources and PDF

MENU()

When you press "m," the Menu() procedure prints what you see in Listing 1 to the SCI.

As you can see, the procedure waits for another command, either "r" or "m." Then the file manager waits again for another command (either "p" or "x" following "r," or "r" or "s" following "m").

If you request a pause, the procedure stays in a loop. The loop exits only when another character is received. Note that this loop executes even when a program isnýt running, but you can fix this with a simple if() statement.

If you request a halt, the procedure sets prg_run to false, changes address prg_addr-3 to false, and jumps back to the main() procedure, which clears the stack and resets RTI. Because prg_run is now false, no program will be run.

Resetting the file manager is accomplished by simply jumping back to the beginning of the main() procedure.

Lastly, Show Settings prints out the value of prg_addr.

PREVIOUSý NEXT