How can I reserve memory and prevent it be used by the compiler?

When you compile with MPLAB® XC8 for a particular device, all the on-chip memory ranges are known by the compiler. If required, you can reduce these memory ranges, and providing the device allows it, specify additional memory to these ranges.

These adjustments can be made using the --RAM and {{--ROM} driver options. If you are using MPLAB X IDE, these options can be accessed from the MPLAB X IDE Build Options, XC8 Linker, Memory Model, RAM Ranges and ROM Ranges.

Please refer the compiler manual for more details about these arguments.

Example : To remove a particular ROM range of memory from the build process, add the option as:
into the ROM ranges field. Doing this will remove the ROM range 1000h-11ffh from the on chip memory.

This option is useful, while writing Bootloader Applications, where the Boot Code has to reserve space for the Main Application and vice versa.

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