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TDA7442 - TDA7442D

4

SOFTWARE SPECIFICATION

Interface Protocol

The interface protocol comprises:

■

A start condition (S)

■

A chip address byte, containing the TDA7442D

■

A subaddress bytes

■

A sequence of data (N byte + acknowledge)

■

A stop condition (P)

ACK = Acknowledge

S = Start

P = Stop

A = Address

B = Auto Increment

4.1 EXAMPLES

4.1.1 No Incremental Bus

The TDA7442D receives a start condition, the correct chip address, a subaddress with the MSB = 0 (no

incremental bus), N-datas (all these data concern the subaddress selected), a stop condition.

4.1.2 Incremental Bus

The TDA7442D receive a start conditions, the correct chip address, a subaddress with the MSB = 1 (in-

cremental bus): now it is in a loop condition with an autoincrease of the subaddress whereas SUBAD-

DRESS from "1XXX1010" to "1XXX1111" of DATA are ignored.

The DATA 1 concern the subaddress sent, and the DATA 2 concerns the subaddress sent plus one sent

in the loop etc, and at the end it receivers the stop condition.

S

1

0

0

0

0

0

A

0

ACK

ACK

DATA

ACK

P

MSB

LSB

MSB

LSB

MSB

LSB

CHIP ADDRESS

D95AU226A

B

DATA

SUBADDRESS

DATA 1 to DATA n

S

1

0

0

0

0

0

A

0

ACK

ACK

DATA

ACK

P

MSB

LSB

MSB

LSB

MSB

LSB

CHIP ADDRESS

D95AU306

0

D3

SUBADDRESS

DATA

X

X

X

D2 D1 D0

S

1

0

0

0

0

0

A

0

ACK

ACK

DATA

ACK

P

MSB

LSB

MSB

LSB

MSB

LSB

CHIP ADDRESS

D95AU307

1

D3

SUBADDRESS

DATA 1 to DATA n

X

X

X

D2 D1 D0