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TDA7409

2.1 Interface Protocol

The interface protocol comprises:

s

a start condition (S)

s

a chip address byte (the LSB bit determines read / write transmission)

s

a subaddress byte

s

a sequence of data (N-bytes + acknowledge)

s

a stop condition (P)

s

the max. CLOCK SPEED is 500kbits/s

S = Start

R/W ="0" -> Receive-Mode (Chip could be programmed by P)

"1" -> Transmission-Mode (Data could be received by P)

ACK = Acknowledge

P = Stop

2.2 TRANSMITTED DATA (send mode)

SM = Soft mute activated

X = Not Used

The transmitted data is automatic updated after each ACK. Transmission can be repeated without new chipaddress.

2.3 Reset Condition

A Power-On-Reset is invoked if the Supply-Voltage is below than 3.5V. After that the following data is written

automatically into the registers of all subaddresses :

The programming after POR is marked bold-face / underlined in the programming tables.

Note : All the blank bits in the following tables are "don't care"-bits.

MSB

LSB

XX

X

X

X

X

X

SM

MSB

LSB

11

1

1

1

1

1

0

S

1

0

0

0

1

0

0

R/W

ACK

ACK

ACK

ACK

P

MSB

LSB

MSB

LSB

MSB

LSB

CHIP ADDRESS

D99AU1044

I3

I0

SUBADDRESS

DATA 1 to DATA n

I2 I1

A3 A2 A1 A0