eorex
EM488M1644VTB
4. Operative Command Table (Note 7)
Current
State
/CS /R /C /W
Addr.
Command
Action
(Note 8)
H
L
L
L
X
H
H
H
X
H
L
X
X
H
L
X
X
DESL
Nop or power down
(Note 8)
NOP or BST
Nop or power down
(Note 9)
ILLEGAL
BA/CA/A10 READ/READA
BA/CA/A10 WRIT/WRITA
(Note 9)
L
ILLEGAL
Idle
L
L
L
L
H
H
H
L
BA/RA
ACT
Row activating
Nop
BA, A10
PRE/PALL
Refresh or self refresh
(Note 10)
L
L
L
H
X
REF/SELF
L
H
L
L
X
H
L
X
H
L
X
X
Op-Code
MRS
DESL
Mode register accessing
Nop
Nop
X
X
NOP or BST
(Note 11)
L
L
L
L
H
H
L
L
L
H
L
BA/CA/A10 READ/READA
BA/CA/A10 WRIT/WRITA
Begin read: Determine AP
(Note 11)
Begin write: Determine AP
(Note 9)
ILLEGAL
Row
Active
H
H
H
L
BA/RA
ACT
(Note 12)
L
BA, A10
PRE/PALL
Pre-charge
(Note 10)
L
L
H
L
L
L
L
L
L
H
L
X
REF/SELF
MRS
ILLEGAL
Op-Code
ILLEGAL
X
H
H
X
H
H
X
H
L
X
X
X
DESL
NOP
Continue burst to end → Row active
Continue burst to end → Row active
Burst stop → Row active
BST
Terminate burst, new read:
(Note 13)
Determine AP
L
H
L
H
BA/CA/A10 READ/READA
BA/CA/A10 WRIT/WRITA
Terminate burst, start write:
(Note 13, 14)
Determine AP
L
L
L
L
L
L
L
H
H
L
H
L
Read
(Note 9)
BA/RA
ACT
ILLEGAL
Terminate burst, pre-charging
(Note 10)
BA, A10
PRE/PALL
L
L
L
L
L
L
H
L
X
REF/SELF
MRS
ILLEGAL
ILLEGAL
Op-Code
Continue burst to end → Write
recovering
H
X
X
X
X
DESL
Continue burst to end → Write
recovering
L
L
H
H
H
H
H
L
X
X
NOP
BST
Burst stop → Row active
Terminate burst, start read:
L
H
L
H
BA/CA/A10 READ/READA
BA/CA/A10 WRIT/WRITA
(Note 13, 14)
Determine AP 7, 8
Write
Terminate burst, new write:
(Note 13)
Determine AP 7
(Note 9)
ILLEGAL
L
L
L
L
L
L
L
H
H
L
H
L
BA/RA
ACT
Terminate burst, pre-charging
(Note 15)
BA, A10
PRE/PALL
L
L
L
L
L
L
H
L
X
REF/SELF
MRS
ILLEGAL
ILLEGAL
Op-Code
Remark H = High level, L = Low level, X = High or Low level (Don't care)
Dec. 2006
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