MPLAB® Harmony v3 Peripheral Libraries on SAM D21: Step 4
Generate Code
When done, before generating the code, click the Save icon in MPLAB® Harmony Configurator (MHC) as shown in the accompanying image.
Save the configuration in its default location when prompted.
Click on the Code Generate button as shown in the accompanying image to start generating code.
Click on the Generate button in the Generate Project window, keeping the default settings as shown in the accompanying image.
If prompted for saving the configuration, click Save.
As the code is generated, MHC displays the progress as shown in the accompanying image.
Examine the generated code as shown in the accompanying image.
MHC will include all the MPLAB Harmony library files and generate the code based on the MHC selections. The generated code would add files and folders to your Harmony project as shown.
Among the generated code, notice the Peripheral Library (PLIB) files generated for Real-Time Clock (RTC), SERCOM 2 (as I²C), SERCOM 3 (as Universal Synchronous Asynchronous Receiver Transmitter (USART)), Direct Memory Access (DMA), External Interrupt Controller (EIC), and PORT peripherals. MHC also generates the template main file (main_d21.c).
Build the project
Click on the Clean and Build icon 
and verify that the project builds successfully. At this point, you are ready to start implementing your application code.
