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STV0676

Overview

1

Overview

1.1

STV0676 co-processor general description

The STV0676 is a digital video processor requiring no external RAM and a minimum of passive

support components to provide a complete USB camera. STV0676 accepts raw digital video data

from a ST VGA or CIF format CMOS sensor and is capable of transferring the resulting JPEG data

to a host PC over USB at rates up to 30 frames per second VGA.

The internal STV0676 architecture consists of a number of separate functional blocks:

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Video processor (VP)

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Video compressor (VC)

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USB control block

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General purpose controller

The VP controls the sensor and processes the raw RGB pixel data into YCbCr images.

This YCbCr data is compressed by the VC.

The USB control block transfers the compressed data to the host PC.

1.2

Video processor (VP)

1.2.1

Sensor interface

The VP interfaces directly to the image sensor. The sensor interface comprises:

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5-wire data bus SDATA[4:0] for receiving both video data and embedded timing references,

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2-wire serial control interface (SSDA, SSCL),

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sensor clock SCLK

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reset circuitry

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sensor suspend control