5V FLASH-ROM. The pin out of both ICs are slightly different and need adaptation. Furthermore, it allows to access different character sets (up to 32/64/128), kernals (up to 16/32/64) or basics (up to ...

COPY /B BASIC.bin +JiffyDOS_C64.bin +JiffyDOS_1541-II.bin MYOWN.ROM To confirm you have the correct image, the BOOT.ROM created must be exactly 32768 or 49152(in case of 32KB C1541 ROM) bytes long.