Texas Instruments TAS3002 SMBus Operation, 6.4.1Block Write Protocol, 6.4.2Write Byte Protocol

Models: TAS3002

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Table 6−3 gives typical values of the wait states that can be expected with the various functions of the part:

Table 6−3. I 2C Wait States

 

SYSTEM SAMPLING FREQUENCY

 

 

 

 

 

Comment

 

32 kHz

44.1 kHz

48 kHz

 

 

 

 

 

Volume

62 ms

49 ms

41 ms

Not dependent on size of change

 

 

 

 

 

Bass

231 ms

167 ms

153 ms

0 to −18 dB

 

 

 

 

 

Treble

231 ms

167 ms

153 ms

0 to −18 dB

 

 

 

 

 

DRC on

300 s

300 s

300 s

 

 

 

 

 

 

Mixer

None

None

None

 

 

 

 

 

 

Loudness

None

None

None

 

 

 

 

 

 

Equalization

15 ms

190 s

300 s

Can occur with each filter

6.4 SMBus Operation

The TAS3002 device supports a subset of the SMBus protocol. With proper programming techniques, it is possible to use the SMBus to set up the TAS3002 device.

6.4.1Block Write Protocol

The TAS3002 device supports the block write protocol that allows up to 32 bytes to be sent as a block. To send a command using this format, the most significant bit (MSB) of the TAS3002 subaddress must be set high and the subaddress (also with MSB set high) must be programmed into the SMBus command byte. This operation signals the TAS3002 device that the next byte is the SMBus byte-count byte. The next byte after the byte count is then entered into the device as the first byte of data.

SMBus

Command Byte

68h

8rh

xx

dd

dd

dd

TAS3002

Subaddress

Byte Count

Data

Data

Data

Address

(r = subaddress)

(Don’t Care)

 

 

 

6.4.2Write Byte Protocol

The TAS3002 device also supports the SMBus write byte protocol. Writing to the main control register (MCR), bass, and treble registers requires using the byte write protocol. To send a command using this protocol, the most significant bit (MSB) of the TAS3002 subaddress must be set high and the subaddress (also with MSB set high) must be programmed into the SMBus command byte. The next byte after the command byte is then entered into the device as the first byte of data.

SMBus

Command Byte

68h

8rh

dd

 

 

 

TAS3002

Subaddress

Data

Address

(r = subaddress)

 

6−4

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Texas Instruments TAS3002 manual SMBus Operation, 6.4.1Block Write Protocol, 6.4.2Write Byte Protocol, 3. I 2C Wait States