TDA7303

Software specification

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4

Software specification

4.1

Interface Protocol

The interface protocol comprises:

●

A start condition (s)

●

A chip address byte, containing the TDA7303 address (the 8th bit of the byte must be

0).

The TDA7303 must always acknowledge at the end of each transmitted byte.

●

A sequence of data (N-bytes + acknowledge)

●

A stop condition (P)

ACK = Acknowledge

S = Start

P = Stop

MAX CLOCK SPEED 100kbits/s

4.2

Subaddress (receive mode)

Ax = 1.25dB steps; Bx = 10dB steps; Cx = 2dB steps; Gx = 3.75dB steps

Table 5.

Chip address

1

MSB

000

10

0

0

LSB

Table 6.

Data bytes

MSB

LSB

FUNCTION

0

0

B2

B1

B0

A2

A1

A0

Volume control

1

1

0

B1B0

A2A1A0

Speaker ATT LR

1

1

1

B1B0

A2A1A0

Speaker ATT RR

1

0

0

B1B0

A2A1A0

Speaker ATT LF

1

0

1

B1B0

A2A1A0

Speaker ATT RF

0

1

0

G1

G0

S2

S1

S0

Audio switch

0

1

1

0

C3

C2

C1

C0

Bass control

0

1

1

1

C3

C2

C1

C0

Treble control