EDE1104ACSE, EDE1108ACSE, EDE1116ACSE
Function Truth Table
The following tables show the operations that are performed when each command is issued in each state of the
DDR SDRAM.
Current state
/CS /RAS /CAS /WE Address
Command
Operation
Notes
Idle
H
L
L
L
L
L
L
L
L
L
L
H
L
L
L
L
L
L
L
L
L
L
×
H
H
H
L
L
L
L
L
L
L
×
H
H
H
L
L
L
L
L
L
L
×
H
L
×
×
DESL
Nop
H
H
L
×
NOP
Nop
BA, CA, A10 (AP)
READ/READA ILLEGAL
1
1
L
BA, CA, A10 (AP)
WRIT/WRITA
ACT
ILLEGAL
H
H
H
L
H
L
BA, RA
Row activating
Nop
BA
PRE
L
A10 (AP)
PALL
Nop
H
H
L
×
REF
Auto-refresh
Self-refresh
Mode register accessing
2
2
2
L
×
SELF
L
BA, MRS-OPCODE
MRS
L
L
BA, EMRS-OPCODE EMRS (1) (2)
Extended mode register accessing 2
Bank(s) active
×
H
L
×
×
DESL
NOP
Nop
Nop
H
H
L
×
BA, CA, A10 (AP)
READ/READA Begin Read
L
BA, CA, A10 (AP)
WRIT/WRITA
ACT
Begin Write
ILLEGAL
H
H
H
L
H
L
BA, RA
1
BA
PRE
Precharge
Precharge all banks
ILLEGAL
L
A10 (AP)
PALL
H
H
L
×
REF
L
×
SELF
ILLEGAL
L
BA, MRS-OPCODE
MRS
ILLEGAL
L
L
BA, EMRS-OPCODE EMRS (1) (2)
ILLEGAL
Continue burst to end
-> Row active
Read
H
L
×
×
×
×
×
DESL
NOP
Continue burst to end
-> Row active
H
H
H
L
L
L
L
L
L
L
L
L
H
H
L
L
L
L
L
L
L
L
L
H
H
H
L
L
L
L
H
L
BA, CA, A10 (AP)
READ/READA Burst interrupt
1, 4
1
BA, CA, A10 (AP)
WRIT/WRITA
ACT
ILLEGAL
ILLEGAL
ILLEGAL
ILLEGAL
ILLEGAL
ILLEGAL
ILLEGAL
ILLEGAL
H
L
BA, RA
1
BA
PRE
1, 8
8
L
A10 (AP)
PALL
H
H
L
×
REF
×
SELF
BA, MRS-OPCODE
MRS
L
BA, EMRS-OPCODE EMRS (1) (2)
Data Sheet E0975E50 (Ver.5.0)
34