128Mb DDR SDRAM
5. Functional Truth Table
Current State
PRECHARGE
STANDBY
CS
L
L
L
L
L
L
ACTIVE
STANDBY
L
L
L
L
L
L
L
READ
L
L
L
L
L
L
L
RAS CAS
H
H
L
L
L
L
H
H
H
L
L
L
L
H
H
H
L
L
L
L
H
L
H
H
L
L
H
L
L
H
H
L
L
H
L
L
H
H
L
L
WE
L
X
H
L
H
L
L
H
L
H
L
H
L
L
H
L
H
L
H
L
X
BA, CA, A
10
BA, RA
BA, A
10
X
Op-Code, Mode-Add
X
BA, CA, A
10
BA, CA, A
10
BA, RA
BA, A
10
X
Op-Code, Mode-Add
X
BA, CA, A
10
BA, CA, A
10
BA, RA
BA, A
10
X
Address
Command
Burst Stop
READ/WRITE
Active
PRE/PREA
Refresh
MRS
Burst Stop
READ/READA
WRITE/WRITEA
Active
PRE/PREA
Refresh
MRS
Burst Stop
READ/READA
ILLEGAL*2
ILLEGAL*2
Bank Active, Latch RA
ILLEGAL*4
AUTO-Refresh*5
Mode Register Set*5
NOP
Begin Read, Latch CA,
Determine Auto-Precharge
Begin Write, Latch CA,
Determine Auto-Precharge
Bank Active/ILLEGAL*2
Precharge/Precharge All
ILLEGAL
ILLEGAL
Terminate Burst
Terminate Burst, Latch CA,
Begin New Read, Determine
Auto-Precharge*3
Action
WRITE/WRITEA ILLEGAL
Active
PRE/PREA
Refresh
Bank Active/ILLEGAL*2
Terminate Burst, Precharge
ILLEGAL
ILLEGAL
Op-Code, Mode-Add MRS
Table 9-1. Functional truth table
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REV. 1.0 November. 2. 2000