Binary compatibility of config files between EP4CE40 and EP4CE55 - Binary compatibility of config files between EP4CE40 and EP4CE55 Due to availability issues, I considering using EP4CE55 instead of EP4CE40 for an existing design. Do the EP4CE40 binaries (*.rbf files) run without modification on the EP4CE55? Replies: Re: Binary compatibility of config files between EP4CE40 and EP4CE55 I have tested and using the same binary file does *NOT* work. I had to generate the bitstream files individually for each part. Replies: Re: Binary compatibility of config files between EP4CE40 and EP4CE55 By right it can be, since 40 has lower Logic element than 55 and can be fitted into it. However, we recommend to regenerate the bitstream based on the actual flash device part number.