Step 5 or 6. Select Device Support
As of MPLAB X IDE v5.00, devices are supported in versioned device packs. If the device pack version is not supported in MPLAB X IDE:
For “Override Default Device Support” checked, you can download the pack support by clicking on the help icon (question mark) and following the instructions. When you download the pack, it will install in Atmel Studio (see figure).
For “Override Default Device Support” checked, you can look in the Atmel Studio pack directory for the correct version. For example:
C:\Program Files
(x86)\Atmel\Studio\7.0\packs\atmel\ATmega_DFP\1.2.209
For “Override Default Device Support” unchecked, you can use the MPLAB X IDE device pack version (the latest) in the project. For example, the MPLAB X IDE project packs would be located under:
C:\Program Files
(x86)\Microchip\MPLABX\v5.xx\packs\Atmel\ATmega_DFP