The ucode (which is loaded on the rsp's instruction memory area) is supposed to not contain data. This is the reason why the CRC should be the same from one rom to another. (I have tried to check the CRC ucode of many frames of a rom and these are always equal). Unfortunately, i have experimented that this is never the case from one rom to another. I think that there are pieces of code that do nothing and that interfere in the CRC's calculation. I think that i will have to disassemble some ucodes to understand why but i have not the time needed now.