S5K433CA Datasheet, PDF (22/25 Pages) Samsung semiconductor – 1/4 Optical Size 640x480(VGA) 3.3V/2.8V VGA CMOS Image Sensor

S5K433CA, S5K433LA
1/4” VGA CMOS IMAGE SENSOR
4. I²C Serial Interface
The I²C is an industry standard serial interface. The I²C contains a serial two-wire half duplex interface that
features bi-directional operation, master or slave mode. The general SDA and SCL are the bi-directional data and
clock pins, respectively. These pins are open-drain type ports and will require a pull-up resistor to VDD. The image
sensor operates in salve mode only and the SCL is input only. The I²C bus interface is composed of following
parts : START signal, 7-bit slave device address (0010001b) transmission followed by a read/write bit, an
acknowledgement signal from the slave, 8-bit data transfer followed by an acknowledgement signal and STOP
signal. The SDA bus line may only be changed while SCL is low. The data on the SDA bus line is valid on the high-
to-low transition of SCL.
SCL
SDA
“0 “0 “1 “0 “0 “0 “1
D7 D6 D5 D4 D5 D2 D1 D0
Start
I²C Bus Address
Write Ack
I2C Register Address
Ack
SCL
SDA
D7 D6 D5 D4 D3 D2 D1 D0
Data to Write
Ack Stop
Figure 10. I²C Bus Write Cycle
SCL
SDA
Start
“0 “0 “1 “0 “0 “0 “1
D7 D6 D5 D4 D5 D2 D1 D0
X
I²C Bus Address
Write Ack
I2C Register Address
Ack
SCL
SDA
“0 “0 “1 “0 “0 “0 “1
D7 D6 D5 D4 D5 D2 D1 D0
Re-Start
I²C Bus Address
Read Ack
Data to be Read
Figure 11. I²C Bus Read Cycle
Ack Stop
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