EM42BM1684RTC
1. Command Truth Table
CKE
n-1
BA0,
BA1
Command
Symbol
/CS /RAS /CAS /WE
A10
A12~A0
N
X
X
X
X
Ignore Command
No Operation
Burst Stop
DESL
NOP
H
H
H
H
H
L
L
L
X
H
H
H
X
H
H
L
X
H
L
X
X
X
V
X
X
X
L
X
X
X
V
BSTH
READ
Read
H
Read with Auto
Pre-charge
READA
WRIT
WRITA
ACT
H
H
H
H
H
X
X
X
X
X
L
L
L
L
L
H
H
H
L
L
L
H
L
V
V
V
V
V
H
L
V
V
V
V
X
Write
Write with Auto
Pre-charge
L
L
H
V
L
Bank Activate
H
H
H
L
Pre-charge Select
Bank
PRE
L
Pre-charge All
Banks
PALL
H
X
L
L
H
L
X
H
X
Mode Register Set
Extended MRS
MRS
H
H
X
X
L
L
L
L
L
L
L
L
OP Code
OP Code
EMRS
H = High level, L = Low level, X = High or Low level (Don't care), V = Valid data input
2. CKE Truth Table
CKE
Item
Command
Symbol
/CS /RAS /CAS /WE Addr.
n-1
H
n
H
L
Idle
Idle
CBR Refresh Command
Self Refresh Entry
REF
L
L
L
L
L
L
H
H
H
X
X
X
X
X
X
X
SELF
H
L
-
-
-
-
H
H
L
L
H
X
X
H
X
X
Self Refresh Self Refresh Exit
L
H
X
Idle
Power Down Entry
Power Down Exit
H
Power
Down
L
H
X
X
X
X
X
H = High level, L = Low level, X = High or Low level (Don't care)
Apr. 2012
13/23
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