eorex
1. Command Truth Table
Command
Ignore Command
No Operation
Burst Stop
Read
Read with Auto Pre-charge
Write
Write with Auto Pre-charge
Bank Activate
Pre-charge Select Bank
Pre-charge All Banks
Mode Register Set
Symbol
DESL
NOP
BSTH
READ
READA
WRIT
WRITA
ACT
PRE
PALL
MRS
CKE
n-1 n
H
H
H
H
H
H
H
H
H
H
H
X
X
X
X
X
X
X
X
X
X
X
/CS
H
L
L
L
L
L
L
L
L
L
L
X
H
H
H
H
H
L
L
L
L
L
EM42AM1684RTA
BA0,
BA1
X
X
X
V
V
V
V
V
V
X
L
/RAS
/CAS
X
H
H
L
L
L
H
H
H
H
L
/WE
X
H
L
H
H
L
H
H
L
L
L
A10
X
X
X
L
H
L
H
V
L
H
L
A12~A0
X
X
X
V
V
V
V
V
X
X
V
H = High level, L = Low level, X = High or Low level (Don't care), V = Valid data input
2. CKE Truth Table
Item
Idle
Idle
Self Refresh
Idle
Power Down
Command
CBR Refresh Command
Self Refresh Entry
Self Refresh Exit
Power Down Entry
Power Down Exit
Symbol
REF
SELF
CKE
n-1 n
H H
H
L
L
H
L
L
H
H
L
H
/CS
L
L
L
H
X
X
/RAS
L
L
H
X
X
X
/CAS
L
L
H
X
X
X
/WE
H
H
H
X
X
X
Addr.
X
X
X
X
X
X
Remark
H = High level, L = Low level, X = High or Low level (Don't care)
Jul. 2006
10/19
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