VmodCAM Reference Manual

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page 4 of 6

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Enable output:

1. R[0x301A] = 0x02CC; parallel enable,

drive pins, start streaming.

Image Processing

Raw sensor data coming from the pixel array is

fed to a color processing pipeline called an

image flow processor (IFP). This is where all

the image processing, correction, scaling,

interpolation, and output formatting algorithms

are applied.

The IFP can also be bypassed, causing the

camera to output the uncompressed raw 10-bit

Bayer data in this mode.

The IFP is controlled indirectly, through

microprocessor variables and the sequencer.

The IFP can be controlled directly by

accessing its hardware registers, but normally

the on-chip microprocessor regularly adjusts

these parameters.

Output Formats

Mode

Byte

D7:D0

RGB565

Odd

Even

RGB555

Odd

Even

RGB444x

Odd

Even

RGBx444

Odd

Even

YUV

4*i

Cb

4*i+1

Y

4*i+2

Cr

4*i+3

Y

Contexts

The microprocessor uses two contexts, each

with their own set of parameters. Context A is

preconfigured for preview mode. Context B is

for snapshot and video capture.

You can set the parameters using the two-wire

interface to command the sequencer to switch

contexts. If the parameters being modified

belong to the active mode, the changes only

take effect after the Refresh and Refresh Mode

commands are executed.

Sequencer

The sequencer is a state machine responsible

for coordinating events triggered by the user.

You can query the current state and instruct

the sequencer to change state.

The sequencer command variable V[0xA103]

accepts the following values:

•

0-Run

•

1-Go to Preview

•

2-Go to Capture

•

3-Go to Standby

•

4-Do lock

•

5-Refresh

•

6-Refresh mode

For the video capture, the Video bit (bit 1)

needs to set in variable V[0xA120]. Otherwise,

the capture state will only take a single

snapshot.

The sequencer state variable V[0xA104] reads:

•

0-Initialize

•

1-Mode Change to Preview

•

2-Enter Preview

•

3-Preview

•

4-Leave Preview

•

5-Mode Change to Capture

•

6-Enter Capture

•

7-Capture

•

8-Leave Capture

•

9-Standby