Datasheet

A6 A5 A4 A3 A2 A1 A0
R/W
ACK A7 A6 A5 A4 A3 A2 A1 A0 ACK D7 D6 D5 D4 D3 D2 D1 D0 ACK
Start
Condition
Stop
Condition
Acknowledge Acknowledge Acknowledge
I CDevice Addressand
2
Read/WriteBit
Subaddress DataByte
T0036-01
D7 D0 ACK
Stop
Condition
Acknowledge
I CDevice Addressand
2
Read/WriteBit
Subaddress LastDataByte
A6 A5 A1 A0 R/W ACK A7 A5 A1 A0 ACK D7 ACK
Start
Condition
Acknowledge Acknowledge Acknowledge
FirstDataByte
A4 A3A6
OtherDataBytes
ACK
Acknowledge
D0 D7 D0
T0036-02
TAS5727
www.ti.com SLOS670 –NOVEMBER 2010
Supplying a subaddress for each subaddress transaction is referred to as random I
2
C addressing. The TAS5727
also supports sequential I
2
C addressing. For write transactions, if a subaddress is issued followed by data for
that subaddress and the 15 subaddresses that follow, a sequential I
2
C write transaction has taken place, and the
data for all 16 subaddresses is successfully received by the TAS5727. For I
2
C sequential-write transactions, the
subaddress then serves as the start address, and the amount of data subsequently transmitted, before a stop or
start is transmitted, determines how many subaddresses are written. As was true for random addressing,
sequential addressing requires that a complete set of data be transmitted. If only a partial set of data is written to
the last subaddress, the data for the last subaddress is discarded. However, all other data written is accepted;
only the incomplete data is discarded.
Single-Byte Write
As shown in Figure 26, a single-byte data-write transfer begins with the master device transmitting a start
condition followed by the I
2
C device address and the read/write bit. The read/write bit determines the direction of
the data transfer. For a data-write transfer, the read/write bit is a 0. After receiving the correct I
2
C device address
and the read/write bit, the DAP responds with an acknowledge bit. Next, the master transmits the address byte or
bytes corresponding to the TAS5727 internal memory address being accessed. After receiving the address byte,
the TAS5727 again responds with an acknowledge bit. Next, the master device transmits the data byte to be
written to the memory address being accessed. After receiving the data byte, the TAS5727 again responds with
an acknowledge bit. Finally, the master device transmits a stop condition to complete the single-byte data-write
transfer.
Figure 26. Single-Byte Write Transfer
Multiple-Byte Write
A multiple-byte data-write transfer is identical to a single-byte data-write transfer except that multiple data bytes
are transmitted by the master device to the DAP as shown in Figure 27. After receiving each data byte, the
TAS5727 responds with an acknowledge bit.
Figure 27. Multiple-Byte Write Transfer
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