Inputs

Data I/O

(Note 1)

Function

OE

DIR

CPAB

CPBA

SAB SBA A

B

H

X

H or L

H or L

X

X

Isolation

HX

N

X

X

X

Input

Input

Clock A

HX

X

N

X

X

Clock B

LH

X

X

L

X

A

LH

N

X

L

X

Input

Output

Clock A

L

H

H or L

X

H

X

A Register to B

LH

N

X

H

X

Clock A

LL

X

X

X

L

B

LL

X

N

X

L

Output

Input

Clock B

L

L

X

H or L

X

H

B Register to A

LL

X

N

X

H

Clock B

H = HIGH Voltage Level

L = LOW Voltage Level

X = Immaterial

Note 1: The data output functions may be enabled or disabled by various signals at the OE and DIR inputs. Data input functions are always enabled; i.e., data at

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

Real Time Transfer

A-Bus to B-Bus

DS100209-5

FIGURE 1.

Real Time Transfer

B-Bus to A-Bus

DS100209-6

FIGURE 2.

Storage from

Bus to Register

DS100209-7

FIGURE 3.

Transfer from

Register to Bus

DS100209-8

FIGURE 4.

3

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