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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

stored and real-time. The examples shown below demon-

strate the four fundamental bus-management functions

that can be performed.

HIGH), A data may be stored in one register and/or B data

may be stored in the other register. When an output func-

tion is disabled, the input function is still enabled and may

be used to store and transmit data. Only one of the two

busses, A or B, may be driven at a time.

Real-Time Transfer

Bus B to Bus A

Real-Time Transfer

Bus A to Bus B

Transfer Storage

Data to A or B

Storage

OE DIR CPAB CPBA SAB SBA

LL

X

X

X

L

OE DIR CPAB CPBA SAB SBA

LH

X

X

L

X

OE DIR CPAB CPBA SAB SBA

LL

X

H or L

X

H

LH

H or L

X

H

X

OE DIR CPAB CPBA SAB SBA

LH



XL

X

LL

X



XL

HX



XX

X

HX

X



XX