I have made a custom board, but I have lost the connection and can no longer program it.
Its a "atmega328p" chip and I use an arduino for programming (arduino as isp)
It has worked fine until I accidentally uploaded #define F_CPU 240000000UL to the chip and now I can no longer talk to board
I have tried to erase the chip with cmd "avrdude -c arduino -b 19200 -p m328p -P COM5 -e"
and: "avrdude -c arduino -b 19200 -p m328p -P COM5 -e -F"
Someone who knows what I can do to make my board work again?