EM488M1644VTF_15 Datasheet, PDF (14/18 Pages) Eorex Corporation – Synchronous DRAM

eorex
EM488M1644VTF
4. Operative Command Table ^{(Note 7)}
Current
State
/CS /R /C /W
Addr.
Command
H XX X
X
DESL
L HH H
X
NOP or BST
L H H L BA/CA/A10 READ/READA
L H L X BA/CA/A10 WRIT/WRITA
Idle
L L H H BA/RA
ACT
L L H L BA, A10
PRE/PALL
L LLH
X
REF/SELF
Action
Nop or power down ^{(Note 8)}
Nop
ILLEGAL ^{(Note 9)}
ILLEGAL ^{(Note 9)}
Row activating
Nop
Auto refresh or self refresh
(Note 10)
Row
Active
Read
L L L L Op-Code
MRS
Mode register accessing
H XX X
X
DESL
Nop
L HH X
X
NOP or BST Nop
L H L H BA/CA/A10 READ/READA Begin read: Determine AP ^{(Note 11)}
L H L L BA/CA/A10 WRIT/WRITA Begin write: Determine AP ^{(Note 11)}
L L H H BA/RA
ACT
ILLEGAL ^{(Note 9)}
L L H L BA, A10
PRE/PALL Pre-charge ^{(Note 12)}
L LLH
X
REF/SELF ILLEGAL ^{(Note 10)}
L L L L Op-Code
MRS
ILLEGAL
H XX X
X
DESL
Continue burst to end → Row active
L HH H
X
NOP
Continue burst to end → Row active
L HH L
X
BST
Burst stop → Row active
Terminate burst, new read:
L H L H BA/CA/A10 READ/READA _{Determine AP (Note 13)}
Terminate burst, start write:
L H L L BA/CA/A10 WRIT/WRITA _{Determine AP (Note 13, 14)}
L L H H BA/RA
ACT
ILLEGAL ^{(Note 9)}
L L H L BA, A10
Terminate burst, pre-charging
PRE/PALL _{(Note 10)}
Write
L LLH
X
L L L L Op-Code
H XX X
X
L HH H
X
L HH L
X
REF/SELF
MRS
DESL
NOP
BST
ILLEGAL
ILLEGAL
Continue burst to end → Write
recovering
Continue burst to end → Write
recovering
Burst stop → Row active
Terminate burst, start read:
L H L H BA/CA/A10 READ/READA _{Determine AP 7, 8 (Note 13, 14)}
Terminate burst, new write:
L H L L BA/CA/A10 WRIT/WRITA _{Determine AP 7 (Note 13)}
L L H H BA/RA
ACT
ILLEGAL ^{(Note 9)}
L L H L BA, A10
Terminate burst, pre-charging
PRE/PALL _{(Note 15)}
L LLH
X
REF/SELF ILLEGAL
L L L L Op-Code
MRS
ILLEGAL
Remark H = High level, L = Low level, X = High or Low level (Don't care)
Jan. 2011
14/18
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