CY7C1470V25_12 CYPRESS [Cypress Semiconductor], CY7C1470V25_12 Datasheet - Page 13

• Manufacturer Part Number: CY7C1470V25_12
• Manufacturer: CYPRESS [Cypress Semiconductor]

Partial Truth Table for Read/Write
The partial truth table for Read/Write for CY7C1470V25 follows.
Document Number: 38-05290 Rev. *O
Notes
Read
Write – no bytes written
Write byte a – (DQ
Write byte b – (DQ
Write bytes b, a
Write byte c – (DQ
Write bytes c, a
Write bytes c, b
Write bytes c, b, a
Write byte d – (DQ
Write bytes d, a
Write bytes d, b
Write bytes d, b, a
Write bytes d, c
Write bytes d, c, a
Write bytes d, c, b
Write all bytes
8. X = “Don't Care”, H = Logic HIGH, L = Logic LOW, CE stands for all chip enables active. BW
9. Write is defined by WE and BW
10. When a write cycle is detected, all I/Os are tri-stated, even during byte writes.
11. Table only lists a partial listing of the byte write combinations. Any combination of BW
that the desired byte write selects are asserted, see Write Cycle Description table for details.
c
a
b
d
and DQP
Function (CY7C1470V25)
and DQP
and DQP
and DQP
[a:d]
c
a
d
b
)
)
)
)
. See Write Cycle Description table for details.
[8, 9, 10, 11]
[a:d]
WE
is valid. Appropriate write will be done based on which byte write is active.
H
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
L
x
= L signifies at least one byte write select is active, BW
BW
H
H
H
H
H
H
H
H
X
L
L
L
L
L
L
L
L
d
BW
LL
H
H
H
H
H
H
H
H
X
L
L
L
L
L
L
L
c
CY7C1470V25
CY7C1472V25
CY7C1474V25
BW
X
H
H
H
H
H
H
H
H
L
L
L
L
L
L
L
L
b
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x
= valid signifies
BW
X
H
H
H
H
H
H
H
H
L
L
L
L
L
L
L
L
a