A new protection strategy was introduced in AD-7200S series. If you try to flash the drive with a different bootcode with the existing bootcode flasher, the program will simply fail. Then crayzcat figured out that you have to toggle a bit in the Optiarc drive using the PLSCSI program. After that the bootcode flasher appeared to work fine, but when you tried to flash the AD-7203S firmware to the drive, the drive will report that it’s still an AD-7200S. Period.
The only known remedy is to flash the drive with OFFICIAL AD-7200S firmware. The drive will work again, except that it won’t recognize any disc any more. At least two members in a Russian forum encountered this problem.
My amateurish guess is that in AD-7200S there is a hidden area that stores the ID of the drive. Even though you succeeded in flashing a different bootcode, the drive is still recognized by its original ID. The problem of failure to recognize disc is caused by the mismatch of bootcode (AD-7203S) and firmware (AD-7200S).
I know I’m not supposed to discuss crossflashing in this forum. I mentioned this problem just to concur with the principle that crossflashing is very dangerous and it may not only void your warranty but also void your drive.