AK8857VQ Datasheet, PDF (71/105 Pages) Asahi Kasei Microsystems – Dual Channel Digital Video Decoder

[AK8857VQ]
7.Device control interface
The AK8857 is controlled via I²C bus control interface, as described below.
[ I2C bus SLAVE Address]
The I²C slave address can be selected by a SELA pin setting of either [1000100] or [1000101].
SELA pin status
Pulldown [Low]
Pullup [High]
Slave Address
MSB
1 00010
1 00010
LSB
0 R/W
1 R/W
[I²C Control Sequence ]
(1) Write sequence
After receiving a write-mode slave address first byte, the AK8857 receives the sub-address in the
second byte and data in the subsequent bytes. The write sequence may be single-byte or multi-byte.
(a) Single-byte write sequence
S
Slave
Address
wA
Sub
Address
A
Data
8-bit
1-
bit
8-bit
1-
bit
8-bit
A Stp
1-
bit
(b) Multi-byte write sequence (m-bytes, sequential write operation)
S
Slave
Address
wA
Sub
Address A
(n)
Data(n)
A
Data
(n+1)
A
‘’’’’’’
Data
(n+m)
8-bit
1-
bit
8-bit
1-
bit
8-bit
1-
bit
8-bit
1-
bit
8-bit
A stp
1-
bit
(2) Read sequence
After receiving a read-mode salve address as the first byte, the AK8857 sends data in the second
and subsequent bytes.
Slave
S Addres
s
w
A
Sub
Address
(n)
A
rS
Slave
Address
R
A
Data1
A
Data
2
A Data3 A
‘’’‘’
8-bit
1 8-bit
1
8-bit
1 8-bit 1 8-bit 1 8-bit 1
’‘’’’’‘’’ ‘’‘ Data n !A stp
8-bit 1
Symbols and abbreviations
S : Start Condition
rS : repeated Start Condition
A : Acknowledge (SDA Low )
!A : Not Acknowledge (SDA High)
stp : Stop Condition
R/W 1 : Read 0 : Write
: Received from master device (normally microprocessor)
: Output by slave device (AK8857)
MS1189-E-01
-71-
2010/12