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CHAPTER 4 BUS INTERFACE
Automatic Wait Cycle of CBR Refresh
Figure 4.17-36 Example of Timing Chart of CBR Refresh Automatic Wait Cycle
[Explanation of operation]
When in serting a CBR refresh automatic wait cycle, set the R3W bit of the RFCR.
Selfrefresh
Figure 4.17-37 Example of Selfrefresh Timing Chart
[Explanation of operation]
Set the SLFR b it of DMCR4 or DMCR5 to "1" to start selfrefresh and set "0" to release it.
When the selfrefresh ends, at least seven idle cycles are ins erted.
In this m anual, selfrefresh is represented by "SR1 to SR3".
R1 R1W R2 R3 R3W R4 idle
CLK
RAS
CAS
wait wait
SR1 SR2 SR3 SR3 SR3 idle
CLK
SLFR bit
RAS
CAS