EM488M1644VTB
____________________________________________
Truth Table
1.Command Truth Table
Command
Symbol CKE
/CS /RAS /CAS /WE BA0, A10
A11,
n-1
n
BA1
X
A9~A0
Ignore Command
No operation
Burst stop
DESL
NOP
H
H
H
H
H
H
H
H
H
H
H
X
X
X
X
X
X
X
X
X
X
X
H
L
L
L
L
L
L
L
L
L
L
X
H
H
H
H
H
L
X
H
H
L
X
H
L
X
X
X
L
X
X
X
V
V
V
V
V
X
X
V
X
BSTH
READ
X
Read
H
H
L
V
Read with auto pre-charge READA
Write WRIT
Write with auto pre-charge WRITA
L
V
H
L
L
V
H
H
H
H
L
H
H
L
V
H
V
L
Bank activate
ACT
PRE
PALL
MRS
L
V
Pre-charge select bank
Pre-charge all banks
Mode register set
L
V
L
L
X
H
L
L
L
L
2. DQM Truth Table
Command
Symbol
CKE
/CS
n-1
n
Data write / output enable
Data mask / output disable
ENB
H
H
x
x
H
L
MASK
Upper byte write enable / output enable
Read
BSTH
READ
READA
WRIT
WRITA
ACT
H
H
H
H
H
H
H
H
H
x
x
x
x
x
x
x
x
x
L
L
L
L
L
L
L
L
L
Read with auto pre-charge
Write
Write with auto pre-charge
Bank activate
Pre-charge select bank
Pre-charge all banks
Mode register set
PRE
PALL
MRS
3. CKE Truth Table
Command
Command
Symbol CKE
/CS /RAS /CAS /WE Addr.
n-1
n
Activating
Any
Clock suspend mode entry
Clock suspend mode
H
L
L
L
X
X
X
L
X
X
X
L
X
X
X
L
X
X
X
H
H
H
X
X
X
X
X
X
X
X
X
X
X
X
Clock suspend Clock suspend mode exit
L
H
H
L
Idle
CBR refresh command
Self refresh entry
Self refresh exit
REF
H
H
L
Idle
SELF
L
L
L
Self refresh
H
H
L
L
H
X
X
X
H
X
X
X
L
H
X
X
Idle
Power down entry
H
L
Power down Power down exit
H
Note : H = High level, L = Low level, X = High or Low level (Don't care), V = Valid data input
12
EOREX [ EOREX CORPORATION ]
