TDA7449L_04 Datasheet, PDF (8/14 Pages) STMicroelectronics – LOW COST DIGITALLY CONTROLLED AUDIO PROCESSOR

TDA7449L
6.2 Incremental Bus
The TDA7449L receive a start conditions, the correct chip address, a subaddress with the B = 1 incremen-
tal 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.
Figure 13.
CHIP ADDRESS
SUBADDRESS
DATA 1 to DATA n
MSB
LSB
MSB
LSB
MSB
S 1 0 0 0 1 0 0 0 ACK X X X 1 D3 D2 D1 D0 ACK
D96AU422
DATA
LSB
ACK P
Table 6. POWER ON RESET CONDITION
INPUT SELECTION
INPUT GAIN
VOLUME
SPEAKER
IN2
28dB
MUTE
MUTE
7 DATA BYTES
Address = 88 HEX (ADDR:OPEN).
Table 7. FUNCTION SELECTION: First byte (subaddress)
MSB
D7
LSB
D6
D5
D4
D3
D2
D1
D0
SUBADDRESS
X
X
X
B
0
0
0
0 INPUT SELECT
X
X
X
B
0
0
0
1 INPUT GAIN
X
X
X
B
0
0
1
0 VOLUME
X
X
X
B
0
0
1
1 NOT USED
X
X
X
B
0
1
0
0 BASS USED
X
X
X
B
0
1
0
1 TREBLE USED
X
X
X
B
0
1
1
0 SPEAKER ATTENUATE "R"
X
X
X
B
0
1
1
1 SPEAKER ATTENUATE "L"
B = 1: INCREMENTAL BUS ACTIVE
B = 0: NO INCREMENTAL BUS
X = DON’T CARE
In Incremental Bus Mode, the three "not used" functions must be addressed in any case. For example to
refresh "Volume = 0dB" and Speaker_R = -40dB", the following bytes must be sent:
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