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2

Function Table

H

= HIGH Voltage Level

X

= Immaterial

L

= LOW Voltage Level

 = LOW-to-HIGH Transition.

Note 1: The data output functions may be enabled or disabled by various signals at the G 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. Also applies to data I/O (A and B: 8-15) and #2 control pins.

Real Time Transfer

A-Bus to B-Bus

Real Time Transfer

B-Bus to A-Bus

Storage from

Bus to Register

Transfer from

Register to Bus

Logic Diagram

Inputs

Data I/O (Note 1)

Output Operation Mode

H

X

H or L

H or L

X

X

Isolation

HX



X

X

X

Input

Input

HX

X



X

X

LH

X

X

L

X

LH



X

L

X

Input

Output

L

H

H or L

X

H

X

LH



X

H

X

L

L

XXX

L

LL

X



X

L

Output

Input

L

L

X

H or L

X

H

LL

X



X

H