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TDA7468

5

SOFTWARE SPECIFICATION

Interface Protocol

The interface protocol comprises:

A start condition (S)

A chip address byte, containing the TDA7468D address

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

6

EXAMPLES

6.1 No Incremental Bus

The TDA7468D receives a start condition, the correct chip address, a subaddress with the B = 0 (no in-

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

6.2 Incremental Bus

The TDA7468D receive a start conditions, the correct chip address, a subaddress with the B = 1 (incre-

mental bus): now it is in a loop condition with an autoincrease of the subaddress whereas SUBADDRESS

from "XXX1000" to "XXX1111" of DATA are ignored.

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

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

Table 5. POWER ON RESET CONDITION

MSB

LSB

D7

D6

D5

D4

D3

D2

D1

D0

1

111

1

1

1

0

S

1

0

0

0

1

0

0

0

ACK

ACK

DATA

ACK

P

MSB

LSB

MSB

LSB

MSB

LSB

CHIP ADDRESS

D96AU420

X

DATA

SUBADDRESS

DATA 1 to DATA n

X

X

B

S

1

0

0

0

1

0

0

0

ACK

ACK

DATA

ACK

P

MSB

LSB

MSB

LSB

MSB

LSB

CHIP ADDRESS

D96AU421

X

D3

SUBADDRESS

DATA

X

X

0

D2 D1 D0

S

1

0

0

0

1

0

0

0

ACK

ACK

DATA

ACK

P

MSB

LSB

MSB

LSB

MSB

LSB

CHIP ADDRESS

D96AU422

X

D3

SUBADDRESS

DATA 1 to DATA n

X

X

1

D2 D1 D0