Lab Exercise 19: Macros with #define


This demo illustrates some of the many uses for macros. Macros created with the #define directive can help simplify and add flexibility to your code. Macros are operations that will be performed by the compiler when it is building your code. So anything you could compute at compile time can be handled by the compiler for you.

Software Tools

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Integrated Development Environment
C Compiler

Exercise Files

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Project and Source Files



Open the Project

Start MPLAB® X IDE, then click on the Open Project Main_Open_Project.png icon on the main toolbar

Navigate to the folder where you saved the exercise files for this class.

Click on the Lab19.X folder.

Select Open Project OpenProjectButton.png.


Debug Project

Click on the Debug Project Main_Debug_Project.png button. This will build and send the program to the simulator.
Click on the Continue Debug_Continue.png button. This begins the simulation.Wait for the UART 1 Output window to finish printing.
Click on the Halt Debug_Pause.png button.



End Debug Session

End the Simulation Session by clicking the Finish Debugger Session Debug_Finish_Debugger_Session.png button.

Clear out the UART 1 Output window (Ctrl + L)

Close the Project.


Much like enumerations, macros can make your code more readable and easier to maintain. However, unlike enumerations, there is much more potential for misuse. So, extreme care must be exercised when writing a macro and when invoking a macro.

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