AK7600 Datasheet, PDF (19/38 Pages) Asahi Kasei Microsystems – 2/6-Channel Audio CODEC with Digital EQ

[AK7600]
1-5. The First byte
The First Byte which includes the Slave-address is input after the Start condition is set, and a target IC device that
will be accessed on the bus is selected by the Slave-address. The Slave-address is configured with the upper 7-bits.
Data of the upper 7-bits is “0011000”. The address bits that select the desired IC are fixed. When the Slave-address
is inputted, an external device that has the identical device address generates an acknowledgement and
instructions are then executed. The 8th bit of the First Byte (lowest bit) is allocated as the R/W Bit. When the R/W
Bit is “1”, the read instruction is executed, and when it is “0”, the write instruction is executed.
Note 17. In this document, there is a case that describes a “Write Slave-address assignment” when both address
bits match and a Slave-address at R/W Bit = “0” is received. There is a case that describes “Read
Slave-address assignment” when both address bits matches and a Slave-address at R/W Bit = “1” is
received.
0
0
1
1
0
0
0
R/W
Slave Address is fixed 30H(write) or 31H(read).
Figure 18. The First Byte Structure
1-6. The Second and Succeeding Bytes
The data format of the second and succeeding bytes of the AK7600 Transfer / Receive Serial data (command code,
address and data in microcontroller interface format) on the I2C BUS are all configured with a multiple of 8-bits.
When transferring or receiving those data on the I2C BUS, they are divided into an 8-bit data stream segment and
they are transferred / received with the MSB side data first with an acknowledgement in-between.
When transferring / receiving A1B2C3 (hex) 24-bit serial data in microprocessor interface format:
(1)I²C Foormat
A1
B2
C3
A
A
8BIT
8BIT
8BIT
A Acknowledge
Figure 19. Division of the Data
Note 18. In this document, there is a case that describes a write instruction command code which is received at the second
byte as “Write Command”. There is a case that describes a read instruction command code which is received at
the second byte as “Read Command”
MS0999-E-00
- 19 -
2008/09