VS6724 Datasheet, PDF (27/118 Pages) STMicroelectronics – 2 Megapixel single-chip camera module

VS6724
Functional description
Mode transitions
Transitions between operating modes are normally controlled by the host by writing to the
Host interface manager control register. Some transitions can occur automatically after a
time out. If there is no activity in the Pause state then an automatic transition to the Stop
state occurs. This functionality is controlled by the Power management register, writing 0xFF
disables the automatic transition to Stop.
The users control allows a transition between Stop and Run, at the state level the system
will transition through a Pause state.
2.8
2.8.1
2.8.2
2.8.3
Video pipe context configuration
Video pipe setup
The VS6724 has a single video pipe, the control of this pipe can be loaded from either of two
possible setups Pipecontext0 and PipeContext1;
PipeContext0 and PipeContext 1, control the operations shown below:
● Image size
● Zoom control
● Pan control
● Crop control
● Image format (YCbCr 4:2:2, RGB565, etc....)
● Image controls (Contrast, Color saturation, Horizontal and vertical flip)
Context switching
In normal operation, it is possible to control which pipe context is used and to switch
between contexts without the need to stop streaming, the change will occur at the next
frame boundary after the change to the register has been made.
For example this function allows the VS6724 to stream an output targeting a display (e.g.
QQVGA RGB 444) then switch to capture an image (e.g. UXGA JPEG) with no need to stop
streaming or enter any other operating mode.
It is important to note the output size selected for both pipe context must be appropriate to
the sensor mode used, i.e. to configure PipeContext0 to QQVGA and PipeContext1 to
UXGA the sensor mode must be set to UXGA.
The register Mode setup allows selection of the pipe context, by default the PipeContext0 is
used.
ViewLive operation
ViewLive is an option which allows a different pipe context to be applied to alternate frames
of the output data.
The controls for VIewLive function are found in the register bank where the fEnable register
allows the host to enable or disable the function and the binitialPipecontext register selects
which pipe context is output first.
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