7/14

TDA7449L

5

SOFTWARE SPECIFICATION

5.1 Interface Protocol

The interface protocol comprises:

■

A start condition (S)

■

A chip address byte, containing the TDA7449L address

■

A subaddress bytes

■

A sequence of data (N byte + acknowledge)

■

A stop condition (P)

Figure 11.

ACK = Acknowledge

S = Start

P = Stop

A = Address

B = Auto Increment

6

EXAMPLES

6.1 No Incremental Bus

The TDA7449L receives a start condition, the correct chip address, a subaddress with the B = 0 (no incre-

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

Figure 12.

SCL

1

MSB

23789

SDA

START

ACKNOWLEDGMENT

FROM RECEIVER

D99AU1033

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