AK4145 Datasheet, PDF (18/27 Pages) Asahi Kasei Microsystems – Digital BTSC Stereo Encoder

[AK4145]
2. WRITE Operations
Set R/W bit = “0” for the WRITE operation of the AK4145.
After receipt the start condition and the first byte, the AK4145 generates an acknowledge, and awaits the second byte
(register address). The second byte consists of the address for control registers of the AK4145. The format is MSB first,
and those most significant 3-bits are “Don’t care”.
*
*
*
A4
A3
A2
A1
A0
(*: Don’t care)
Figure 11. The Second Byte
After receipt the second byte, the AK4145 generates an acknowledge, and awaits the third byte. Those data after the
second byte contain control data. The format is MSB first, 8bits.
D7
D6
D5
D4
D3
D2
D1
D0
Figure 12. Byte structure after the second byte
The AK4145 is capable of more than one byte write operation in one sequence.
After receipt of the third byte, the AK4145 generates an acknowledge, and awaits the next data again. The master can
transmit more than one words instead of terminating write cycle after the first data word is transferred. After the receipt of
each data, the internal 5bits address counter is incremented by one, and the next data is taken into next address
automatically. If the address exceeds 05H prior to generating stop condition, the address counter will “roll over” to 00H
and the previous data will be overwritten.
S
T
A Slave
R Address
T
Register
A ddr ess(n)
Data(n)
Dat a(n+1 )
S
T
Data(n+x) _O
P
SD A
S
P
A
A
A
A
C
C
C
C
K
K
K
K
Figure 13. WRITE Operation
MS0982-E-01
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2010/09