
CHAPTER 5 MEMORY ACCESS CONTROL FUNCTION
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User’s Manual U14359EJ4V0UM
(3) Refresh timing
Figure 5-18. CBR Refresh Timing (SDRAM)
D0 to D15 (I/O)
WE (output)
OE (output)
RD (output)
SDCAS (output)
SDRAS (output)
CSn (output)
BCYST (output)
A0 to A9, A11 to A23
(output)
A10 (output)
SDCLK (output)
ALLPRE TW
TW
TREF
TBCW
TBCW
TW
TBCW
TBCW
TBCW
TBCW
TBCW
TBCW
TI
TI
SDCKE (output)
LDQM (output)
UDQM (output)
All-bank precharge
command
Refresh command
H
H
H
BCW
×
4clk
Remarks 1.
The number of wait states set by the BCW1n and BCW0n bits of the SCRn register
×
4 clocks will
be inserted in the BCW
×
4 clk period.
2.
n = 1, 3, 4, 6