For those with a Dallas installed not wishing to remove the clock chip here is a simple mod I found on the Internet.
Cut/file (or melt in my case but not advised >:) ) the sides to expose the contacts.
Solder on the + and - wires to the battery connector. Insert the battery and reset the Nvram.
The original link : http://www.mcamafia.de/mcapage0/dsrework.htm
This is what someone else done and it worked fine for me. Obviously the other way is tidier.
This is the inside of the mk chip after I ripped it open. As you can see a similar process can be achieved on the side of the u56.
Note: if the clock chip has a distorted case then the battery inside has leaked and needs replacing.
64bit: Jaguar + CD unit + Alpine, tap tap, jag link,pro controller
32bit: Abaq(ATW800) + Charity(Blossom), Falcon CT63, Falcon 030 (*2), TT030
16bit: MegaSTE, STe, MegaST, MegaST4, STFM, STF, Stacy
Life: its all about the journey.