SH7760 Datasheet, PDF (368/1345 Pages) Renesas Technology Corp – SuperHTM RISC engine

Auto-refreshing is performed in normal operation, in sleep mode, and at a manual reset.
Also, if both areas 2 and 3 are set to the synchronous DRAM, auto-refreshing of area 2 is
performed after area 3.
RTCNT value
RTCOR-1
RTCNT cleared to 0 when
RTCNT = RTCOR
H'00000000
RTCSR.CKS2–0
= 000 ≠ 000
Refresh
request
External bus
Refresh request cleared
by start of refresh cycle
Auto-refresh cycle
Figure 10.27 Auto-Refresh Operation
Time
CKIO
TRr1 TRr2 TRr3 TRr4 TRrw TRr5 Trc Trc Trc
CSn
RD/WR
RAS
CASS
DQMn
D31−D0
BS
CKE
Figure 10.28 Synchronous DRAM Auto-Refresh Timing
Rev. 1.0, 02/03, page 318 of 1294