Ryszard,

CBR=CAS Before RAS.

Normally the Row Address Strobe (RAS) precedes the Column Address Strobe (CAS) by tRCD (page 11 READ CYCLE). CBR uses an internal refresh (row address) counter which allows a simple refresh cycle where CAS and RAS are basically swapped in order of occurance without any refresh address needed.

Check your application. If you are going to be cycling through memory all the time (typical of audio/video applications) the act of continuous reading or writing will perform as your refresh.

regards,
p