Epson S1C33L03 User Manual

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VI SDRAM CONTROLLER BLOCK: SDRAM INTERFACE
B-VI-2-16
EPSON
S1C33L03 FUNCTION PART
Figure 2.12 shows an example of a timing chart in cases where the row address is varied during burst read.
BCLK
Command
SDCKE
#SDCEx
#SDRAS
#SDCAS
#SDWE
SDBA[1:0]
SDA[10]
SDA[12:11, 9:0]
LDQM/HDQM
DQ[15:0]
ACTV
NOP
H
NOP
NOP
NOP
PRE
NOP
READ
BA
BA
ROW1
D
(n)
D
(n+1)
D
(n+2)
D
(0)
D
(1)
D
(2)
t
RCD
t
RP
t
RCD
t
RAS
t
RP
CAS latency
 = 2
CAS latency
 = 2
ROW1
COLn
BA
ACTV NOP
PRE
NOP
READ
BA
BA
ROW2
ROW2
COL0
BA
Figure 2.12  Changing Row Address During Burst Read
Single Read/Single Write
If the burst length is set to "1" (SDRBL[1:0] = "00"), the SDRAM controller reads data from the SDRAM in a
single operation.
When writing to the SDRAM, data are always written in a single operation, no matter what burst length is selected.
BCLK
Command
SDCKE
#SDCEx
#SDRAS
#SDCAS
#SDWE
SDBA[1:0]
SDA[10]
SDA[12:11, 9:0]
LDQM/HDQM
DQ[15:0]
ACTV
NOP
H
NOP
NOP
PRE
NOP
READ
BA1
BA1
ROW1
D
(1)
t
RCD
t
RP
t
RCD
t
RP
CAS latency
 = 2
ROW1
COL1
BA1
ACTV NOP
PRE
NOP
BA2
BA2
ROW2
ROW2
COL2
BA2
D
(2)
WRIT
Figure 2.13  Single Read to Single Write (different page)
BCLK
Command
SDCKE
#SDCEx
#SDRAS
#SDCAS
#SDWE
SDBA[1:0]
SDA[10]
SDA[12:11, 9:0]
LDQM/HDQM
DQ[15:0]
ACTV
NOP
H
NOP
NOP
NOP
PRE
NOP
READ
BA
BA
ROW1
D
(n)
D
(n+1)
D
(n+2)
D
(m)
t
RCD
t
RP
CAS latency
 = 2
ROW1
COLn
BA
WRIT NOP
PRE
BA
COLm
BA
Figure 2.14  Burst Read to Single Write (same page)