I have been trying to flash the firmware on atmega32u4 with no success.
I ran
$ make -f makefile dfu
dfu-programmer atmega32u4 erase --force
dfu-programmer: no device present.
make: *** [../../tmk_core/rules.mk:424: dfu] Error 3
It keep saying no device present. I did enter DFU mode. Any idea what else am I missing?