VS6663CC Datasheet, PDF (21/63 Pages) STMicroelectronics – 1.3 megapixel camera module

VS6663CC
4
Camera control interface (CCI)
Camera control interface (CCI)
This chapter specifies the camera control interface (CCI). The I²C-type interface uses 1.8 V
I/O with two signals: serial data line (SDA) and serial clock line (SCL). CCI is used for
control data transfer. Clock signal (SCL) generation is performed by the master device (the
camera module is a slave device). The master device initiates data transfer. The CCI bus on
the camera module has a maximum speed of 400 Kbits/s and has a software switchable
device address.
Any internal register that can be written to, can also be read from. There are also read only
registers that contain device status information, (for example, design revision details). A
read instruction from an un-used register location will return the value 0x00. A read
instruction from the manufacturers specific registers may return any value. A write
instruction to a reserved or unused register location is illegal and the effect of such a write is
undefined. It is the responsibility of the host system to only write to register locations which
have been defined.
4.1
Valid register data types
The contents of the registers can represent a number of different data types (see Table 9).
The register map uses this coding to help with the interpretation of the contents of each
register.
Table 9. Valid register data types
Data type
Name
Range
Description
8UI
8-bit unsigned integer
0 to 255
-
8SI
8-bit signed integer
-128 to 127
Two’s complement notation
16UI
16-bit unsigned integer
0 to 65535
-
16SI
16UR
16-bit signed integer
16-bit unsigned iReal
-32768 to 32767
0 to 255.99609375
Two’s complement notation
08.08 fixed point number. 8
integer bits (MS Byte), 8
fractional bits (LS Byte)
16SR
16-bit signed iReal
-128 to 127.9960375
Two’s complement
notation, 8 fractional bits
32SF
32-bit IEEE floating-point
number
As per IEEE 754
As per IEEE 754. 1 sign bit,
8 exponent bits, 23
fractional bits
8C or 16C 8-bit or 16-bit Coded
-
This indicates that the
value is decoded to select
one of several functions or
modes.
8B or 16B 8 or 16 Bits
-
Each bit represents a
specific function or mode.
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