EM484M1644VTD
eorex
5. Command Truth Table for CKE
CKE
Current State
/CS /R /C /W
Addr.
Action
n-1
n
INVALID, CLK(n-1) would exit self
refresh
Self refresh recovery
Self refresh recovery
ILLEGAL
ILLEGAL
Maintain self refresh
Idle after tRC
Idle after tRC
ILLEGAL
ILLEGAL
ILLEGAL
H
X
X
X
X
X
X
L
L
L
L
L
H
H
H
H
H
H
H
H
H
H
H
H
L
H
H
H
H
L
H
L
L
L
X
H
L
L
L
H
L
L
L
X
H
H
L
X
X
H
H
L
X
H
H
L
X
H
L
X
X
X
H
L
X
X
H
L
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Self Refresh
Self Refresh
Recovery
L
L
L
ILLEGAL
ILLEGAL
ILLEGAL
X
INVALID, CLK(n-1) would exit
power down
Exit power down → Idle
Maintain power down mode
Refer to operations in Operative
Command Table
H
X
X
X
X
X
X
Power Down
L
L
H
L
X
X
H
L
L
L
L
H
L
X
X
X
H
L
L
L
X
H
L
X
X
X
X
H
L
X
X
X
X
X
H
L
X
X
X
X
X
H
H
H
H
H
H
H
H
H
H
H
H
H
L
X
Refresh
L
Op-Code
X
X
H
Refer to operations in Operative
Command Table
Both Banks
Idle
L
L
L
Self refresh (Note 17)
Refer to operations in Operative
Command Table
Power down (Note 17)
Refer to operations in Operative
Command Table
Power down (Note 17)
L
H
H
L
L
L
L
H
X
L
L
L
L
L
Op-Code
X
X
X
X
X
X
X
X
X
X
X
X
H
Row Active
L
X
H
X
X
X
X
X
X
X
X
X
Refer to operations in Operative
Command Table
H
Begin clock suspend next cycle
(Note 18)
Any State Other
than Listed above
H
L
X
X
X
X
X
L
L
H
L
X
X
X
X
X
X
X
X
X
X
Exit clock suspend next cycle
Maintain clock suspend
Remark: H = High level, L = Low level, X = High or Low level (Don't care)
Notes 17: Self refresh can be entered only from the both banks idle state.
Power down can be entered only from both banks idle or row active state.
Notes 18: Must be legal command as defined in Operative Command Table
Apr. 2014
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