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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
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
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
1
D3
SUBADDRESS DATA 1 to DATA n
X
X
X
D2 D1 D0
