VV6404 datasheet(29/54 Pages) STMICROELECTRONICS

29 / 54 page

VV5404 & VV6404

CD5404-6404F-A

29/54

5.5

The Programmers Model

There may be up to 128, 8-bit registers within the camera, accessible by the user via the serial interface. They are

grouped according to function with each group occupying a 16-byte page of the location address space. There may

be up to eight such groups, although this scheme is purely a conceptual feature and not related to the actual hardware

implementation, The primary categories are given below:

•

Status Registers (Read Only).

•

Setup registers with bit significant functions.

•

Exposure parameters that influence output image brightness.

•

System functions and analogue test bit significant registers.

Any internal register that can be written to can also be read from. There are a number of read only registers that

contain device status information, (e.g. design revision details).

Names that end with H or L denote the most or least significant part of the internal register. Note that unused locations

in the H byte are packed with zeroes.

STMicroelectronics sensors that include a 2-wire serial interface are designed with a common address space. If a

is referred to as reserved. If the user attempts to read from any of these reserved locations a default byte will be

read back. In VV6404 this data is the LSByte of the device status word, address 000_0000. A write instruction to a

reserved (but unused) location is illegal and would not be successful as the device would not allocate an internal

VV6404 Datasheet(PDF) 29 Page - STMicroelectronics