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Functional Description

In the transceiver mode, data present at the HIGH imped-

ance port may be stored in either the A or B register or

both.

The select (SAB, SBA) controls can multiplex stored and

real-time.

The examples below demonstrate the four fundamental

bus-management functions that can be performed with the

LVTH652.

Data on the A or B data bus, or both can be stored in the

internal D-type flip-flop by LOW-to-HIGH transitions at the

appropriate Clock Inputs (CPAB, CPBA) regardless of the

Select or Output Enable Inputs. When SAB and SBA are in

the real time transfer mode, it is also possible to store data

without using the internal D-type flip-flops by simulta-

neously enabling OEAB and OEBA. In this configuration

each Output reinforces its Input. Thus when all other data

sources to the two sets of bus lines are in a HIGH imped-

ance state, each set of bus lines will remain at its last state.

Real-Time Transfer

Bus B to Bus A

Storage

Real-Time Transfer

Bus A to Bus B

Transfer Storage

Data to A or B

OEAB

OEBA

CPAB

CPBA

SAB

SBA

L

L

XXX

L

OEAB

OEBA

CPAB

CPBA

SAB

SBA

XH



XXX

LX

X



XX

LH



XX

OEAB

OEBA

CPAB

CPBA

SAB

SBA

HH

X

X

L

X

OEAB

OEBA

CPAB

CPBA

SAB

SBA

H

L

H or L

H or L

H

H