Datasheet

PICkit™ 3 Debug Express Lessons

FIGURE 3-5: THE PROJECT WINDOW

To complete the project setup, we will add a Linker Script and microcontroller header

file to the project. A Linker Script is required to build the project. It is a command file for

the linker, and defines options that describe the available memories on the target

microcontroller. There are four example linker files for the microcontroller:

Add the Linker Script by selecting menu Project > Add files to project…

. In the “Files of

type” dropdown box, select “Linker Scripts (*.lkr)” as shown in Figure 3-6. Browse

to the Linker Scripts directory C:\MCC18\lkr and open the 18f45k20i.lkr file as

the debugger will be used in later lessons.

Files can also be added by right-clicking in the Project window. Right-click on the

“Header Files” folder and select Add Files… from the pop-up menu. Browse to the

MPLAB C header file directory C:\MCC18\h and open the p18f45k20.h header file.

The Project window now looks like Figure 3-7.

It is important to note that the file selected in the directory it resides in will be added to

the project, so modifying it will modify the original file. If this is not desired, open the file

and use File > Save As…

to save a new copy in the current project directory and then

add the new file to the project. As a final step use File > Save Workspace

to save the

project and its working environment.

18f45k20.lkr Basic Linker Script file for compiling a memory image in

non-extended processor mode. (More on the Extended mode in a

later lesson.)

18f45k20_e.lkr Linker Script file for compiling using Extended mode.

18f45k20i.lkr Linker Script file for use when debugging. These Linker Scripts

prevent application code from the using the small areas of memory

reserved for the debugger.

18f45k20i_e.lkr Linker Script file for debugging in Extended mode.