feather m4 cache

Author: ladyada

boards.txt

@@ -365,7 +365,7 @@ adafruit_feather_m4.build.usb_product="Adafruit Feather M4"
 adafruit_feather_m4.build.usb_manufacturer="Adafruit LLC"
 adafruit_feather_m4.build.board=FEATHER_M4
 adafruit_feather_m4.build.core=arduino
-adafruit_feather_m4.build.extra_flags=-D__SAMD51J19A__ -D__SAMD51__ {build.usb_flags} -D__FPU_PRESENT -DARM_MATH_CM4 -mfloat-abi=hard -mfpu=fpv4-sp-d16
+adafruit_feather_m4.build.extra_flags=-D__SAMD51J19A__  -DADAFRUIT_FEATHER_M4_EXPRESS  -D__SAMD51__ {build.usb_flags} -D__FPU_PRESENT -DARM_MATH_CM4 -mfloat-abi=hard -mfpu=fpv4-sp-d16
 adafruit_feather_m4.build.ldscript=linker_scripts/gcc/flash_with_bootloader.ld
 adafruit_feather_m4.build.openocdscript=openocd_scripts/arduino_zero.cfg
 adafruit_feather_m4.build.variant=feather_m4
@@ -375,3 +375,7 @@ adafruit_feather_m4.build.pid=0x8022
 adafruit_feather_m4.bootloader.tool=openocd
 adafruit_feather_m4.bootloader.file=metroM4/bootloader.bin
 adafruit_feather_m4.compiler.arm.cmsis.ldflags="-L{build.variant.path}" -larm_cortexM4lf_math -mfloat-abi=hard -mfpu=fpv4-sp-d16
+adafruit_feather_m4.menu.cache.on=Enabled
+adafruit_feather_m4.menu.cache.on.build.cache_flags=-DENABLE_CACHE
+adafruit_feather_m4.menu.cache.off=Disabled
+adafruit_feather_m4.menu.cache.off.build.cache_flags=