@xdanger
Hello there, welcome to the boards
Glad you have found the retr0liciousness of the Amiga1200 now its time to help you use it
Firstly the CIAs in the A1200 are nothing like that in other previous models of Amiga, they are integrated into VSLI chips. however i must thank you for the hardware pr0n of the A500's CIA's very nice indeed
Now the Floppy drive has very little do with CIA's as these are mainly for timing latches of memory locations such like chip ram, pcmcia, joyport etc (mouse port is controlled by paula).
As you have discovered, FDD's usually get incredibly cruddy and will refuse to work, sometimes the only way is completely strip and clean the drive. I have read some where, where some clever spark managed to change the heads of the FDD from one of a PC FDD and it worked flawlessly. But when a drive is beyond repair it is because the drive motor that fails to spin properly and hence the sync constantly fails (error city!)
Changing the FDD is perhaps the best thing to do at this point, once you have this you can then getto grips with cleaning the old one, and with a little luck you could end up with a working spare to sell or keep
again, welcome to the boards theres so much mischief to get upto so kick back, releax and enjoy the chocolate coated retroness that this fair board provides