Create the Project

After installing the software, connect the PIC24F Curiosity Development Board to a USB port on your computer. Create a new standalone project in MPLAB^® X for a PIC124FJ128GA204. The PIC124FJ128GA204 is the microcontroller on the PIC24F Curiosity Development Board. When the project creation wizard asks for a hardware tool (Step 2 in the New Project window), select the PIC24F Curiosity Board as displayed below.

After the project has been created, the Projects tab in the upper-left corner of the IDE shows that the project has been created with no source or header files.

Open MCC

Open MCC under the Tools > Embedded menu of MPLAB X IDE.

MCC will place a Resource Management tab on the left-hand side of the IDE. Inside this tab, you will see a section for Project Resources and Device Resources. For each MCC-generated project, you will need to verify/modify the System Modules under the Project Resources window.

Set the Project Resources

There are three system elements which need attention:

• Interrupt Module: controls the MCU's interrupts.
• Pin Module: configures the I/O pins.
• System Module: selects and configures the clock source for the MCU.

Interrupt Module

This project does not use interrupts so this section will not be used.

System Module

The System Module allows the user to configure the MCU's clock, the Watchdog Timer (WDT), and make changes to the debug pin assignments. This feature of the PIC24F MCU has numerous options, which are typically modified to fit the needs of the application. MPLAB^® Code Configurator (MCC) provides default settings if no changes are selected by the developer. For this lab, accept the default clock settings:

• 8 MHz Internal Free Running Oscillator with no Prescaler, but a 1:2 Postscaler (4 MHz Fosc)
• Watchdog Timer - disabled
• Unchanged debug pins

To verify the default settings, click on the System Module tab and verify the following selections have been made:

Pin Module

Click on the Pin Module in the Project Resources window. Three windows will open in the IDE:

• Pin Module Window
• Package View
• Grid View

The Pin Manager: Grid View window shows that pins RB1 and RB0 have been reserved as the programming pins.

We will now set the pin connected to LED1 (RA9) as an output and the pin connected to S1 (RC9) as an input. In the Grid View window, click on the output box under RA9 and the input box under RC9. The grid view will display the "padlocks" in green indicating these pins have been configured for use.

• Ensure that RA9 is set as an output pin.
• Rename RA9 as LED1.
• Ensure that RC9 is set as an input pin.
• Rename RC9 as S1.

Generate Code

To generate the code, click the Generate button on the MCC window.

The projects tab will show the source and header files created by MCC.

The main(void) is located within the main.c file. main(void) calls the MCC generated SYSTEM_Initialize() function before it enters the while(1) loop.

SYSTEM_Initialize() in turn calls PIN_MANAGER_Initialize() to configure the I/O pins. PIN_MANAGER_Initialize() loads the TRISA and TRISC registers with the vaues needed to set RA9 as an output pin and RC9 as an input pin.

Modify the program to use the value of S1 to drive LED1

We will now main modify main.c to drive RA9 (LED1) with the value of pin RC9 (S1). An inspection of MCC generated header file pin-manager.h, shows MCC has created several control functions for the I/O pins we have configured and named. Among these macros are LED1_SetLow, LED1_SetHigh, and S1_GetValue().

Make the following modifications to main.c:

1. Insert the text #include "mcc_generated_files/mcc.h" near the top of the file.
2. Insert LED1_SetLow and LED2_SetHigh into main().

main.c

#include "mcc_generated_files/system.h"
#include "mcc_generated_files/mcc.h"   
/*
                         Main application
 */
int main(void)
{
    // initialize the device
    SYSTEM_Initialize();

    while (1)
    {
        if (S1_GetValue())
                LED1_SetLow();
         else
                LED1_SetHigh();
    }

    return 1;
}

Build, Download, and Run the code

After the board is pogrammed neither LED1 or LED2 will be on; they are both turned off.