If you have the plugin installed and it doesn't let you select PBP, then make sure the toolchain settings are correct.Then I have installed MPLAB X 4.05 and ticked the PBP tool chainbox in the plugins list. Then I tried to make a new project but even if the PBP compiler is listed I cannot select in the list of compilers when MPLAB ask it.
From the MPLABX main menu select 'Tools | Options | Embedded | Build Tools'
Make sure PICBASIC PRO is shown in the 'Toolchain' listbox. If it isn't then 'Add...' and browse to the PBP folder. It should recognize it, and then select 'OK'
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