15:19 <promach3> 1. What does it exactly mean by _precharge period is determined by the last PRECHARGE command issued to the bank._ ?

15:19 <promach3> 2. Why the maximum absolute interval between any REFRESH command and the next REFRESH command is **nine times** the maximum average interval refresh rate. ?

15:25 <hell__> promach3: answering your second question: refreshing the memory exactly every tREFI time is impractical

15:28 <hell__> so it's possible to postpone up to eight refresh commands, or do extra refresh cycles in preparation for a long operation

15:33 <promach3> hell__: what is *do extra refresh cycles in preparation for a long operation* ?

15:34 <hell__> this flexibility is especially useful when controlling the memory through software (e.g. during memory initialization): maintaining a perfect timing in software is usually impractical

15:34 <promach3> What do you exactly mean by postpone up to eight refresh commands ?

15:35 <hell__> I mean what the DDR3 spec says (JESD79-3F is the latest revision)

15:42 <promach3> hell__: which page number inside JESD79-3F ?

15:56 <hell__> I'd suggest reading the whole document

15:56 <hell__> it's not that long

16:01 <promach3> it is 226 pages long

16:01 <Hoernchen> lol

16:26 <hell__> Self-refresh is another story

17:19 <hell__> yes, this is what I was saying earlier

17:20 <hell__> Figure 60 shows how refresh commands get postponed