AK4682 Datasheet, PDF (31/43 Pages) Asahi Kasei Microsystems – Multi-channel CODEC with 2Vrms Stereo Selector

[AK4682]
1-3. ACKNOWLEDGE
ACKNOWLEDGE is a software convention used to indicate successful data transfers. The transmitting device will
release the SDA line (HIGH) after transmitting eight bits. The receiver must pull down the SDA line during the
acknowledge clock pulse so that that it remains stable “L” during “H” period of this clock pulse. The AK4682 will
generates an acknowledge after each byte has been received.
In the read mode, the slave, the AK4682 will transmit eight bits of data, release the SDA line and monitor the line for an
acknowledge. If an acknowledge is detected and no STOP condition is generated by the master, the slave will continue
to transmit data. If an acknowledge is not detected, the slave will terminate further data transmissions and await the
STOP condition.
Clock pulse
for acknowledge
SCL FROM
MASTER
1
8
9
DATA
OUTPUT BY
TRANSMITTER
DATA
OUTPUT BY
RECEIVER
START
CONDITION
Figure 16. Acknowledge on the I²C-bus
not acknowledge
acknowledge
1-4. FIRST BYTE
The first byte, which includes seven bits of slave address and one bit of R/W bit, is sent after the START condition. If
the transmitted slave address matches an address for one of the device, the receiver who has been addressed pulls down
the SDA line.
The most significant five bits of the slave address are fixed as “00100”. The next two bits are “10”. These two bits
identify the specific device on the bus. The eighth bit (LSB) of the first byte (R/W bit) defines whether a write or read
condition which the master requests. A “1” indicates that the read operation is to be executed. A “0” indicates that the
write operation is to be executed.
0
0
1
0
0
1
0
R/W
Figure 17. The First Byte
MS0610-E-01
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2007/07