AK7755EN_16 Datasheet, PDF (80/109 Pages) Asahi Kasei Microsystems – DSP with Mono ADC Stereo CODEC + Mic/Lineout Amp

[AK7755]
1-3. Repeated Start Condition
When a Start condition is received again instead of a Stop condition, the bus changes to a Repeated
Start condition. A Repeated Start condition is functionally the same as a Start condition.
SCL
SDA
START CONDITION
Repeated Start CONDITION
Figure 64. Repeated Start Conditions (I²C)
1-4. Acknowledge
An external device that is sending data to the AK7755 releases the SDA line (“H”) after receiving one
byte of data. An external device that receives data from the AK7755 then sets the SDA line to “L” at
the next clock. This operation is called “acknowledgement”, and it enables verification that the data
transfer has been properly executed. The AK7755 generates an acknowledgement upon receipt of a
Start condition and a Slave address. For a write instruction, an acknowledgement is generated
whenever receipt of each byte is completed. For a read instruction, succeeded by generation of an
acknowledgement, the AK7755 releases the SDA line after outputting data at the designated address,
and it monitors the SDA line condition. When the Master side generates an acknowledgement without
sending a Stop condition, the AK7755 outputs data at the next address location. When no
acknowledgement is generated, the AK7755 ends data output (not acknowledged).
Clock pulse
for acknowledge
SCL FROM
MASTER
DATA
OUTPUT BY
TRANSMITTER
DATA
OUTPUT BY
RECEIVER
START
CONDITION
1
8
Figure 65. Generation of Acknowledgement (I²C)
9
not acknowledge
acknowledge
014006643-E-00
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2014/10