sam4s sps-1000 new battery still not working?

You must RAM clear it and re-program after replacing the battery since the memory has been scrambled from the low voltage of the old battery. Once you RAM clear it, it should hold the new data just fine.
If you need the programming manual, one of the users has it here:

http://the-checkout-tech.com/manuals/cashregisters/Samsung_SPS-1000_programming_manual.html

Registerman
October 2013