Functional Table
OE
D SELAB SELBA CLKAB CLKBA A0–A7 B0–B7
Function
H
X
X
X
H or L H or L
Isolation
H
X
X
X
LH
X
Input Input CLK A Data into A
H
X
X
X
X
LH
CLK B Data into A Reg.
L
H
L
X
X
X
A to B – Transparent
L
H
L
X
LH
X
CLK A Data into A Reg.
L
H
H
X
H or L
X
Input Output A Reg. to B (Storage)
L
H
H
X
LH
X
CLK A Data into A Reg. and B output
L
L
X
L
X
X
B to A – Transparent
L
L
X
L
X
LH
CLK B Data into B Reg.
L
L
X
H
X
H or L Output Input B Reg. to A (Storage)
L
L
X
H
X
LH
L = Low
H = High
LH = Low to High transition
X = Don’t Care
CLK B Data into B Reg.and A output
Logic Diagram
Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays.
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