Inputs

Inputs/Outputs (Note 1)

Operating Mode

OEAB

OEBA

CPAB

CPBA

SAB

SBA

A

B

L

H

H or L

H or L

X

X

Input

Input

Isolation

L

H

N

N

X

X

Store A and B Data

X

H

N

H or L

X

X

Input

Not Specified

Store A, Hold B

H

H

N

N

X

X

Input

Output

Store A in Both Registers

L

X

H or L

N

X

X

Not Specified

Input

Hold A, Store B

L

L

N

N

X

X

Output

Input

Store B in Both Registers

L

L

X

X

X

L

Output

Input

Real-Time B Data to A Bus

L

L

X

H or L

X

H

Store B Data to A Bus

H

H

X

X

L

X

Input

Output

Real-Time A Data to B Bus

H

H

H or L

X

H

X

Stored A Data to B Bus

H

L

H or L

H or L

H

H

Output

Output

Stored A Data to B Bus and

Stored B Data to A Bus

H = HIGH Voltage Level

L = LOW Voltage Level

X = Immaterial

N = LOW to HIGH Clock Transition

Note 1: The data output functions may be enabled or disabled by various signals at OEAB or OEBA inputs. Data input functions are always enabled, i.e., data at

the bus pins will be stored on every LOW to HIGH transition on the clock inputs.

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