A typical 'boards.txt' entry

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xmega64d4.name=ATXMega64D4

xmega64d4.upload.protocol=arduino
xmega64d4.upload.maximum_size=65536
xmega64d4.upload.speed=115200
xmega64d4.build.mcu=atxmega64d4
xmega64d4.build.f_cpu=32000000L
xmega64d4.build.core=xmega
xmega64d4.build.variant=xmega64d4

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