VV5404 Datasheet, PDF (14/54 Pages) List of Unclassifed Manufacturers – CIF FORMAT DIGITAL IMAGE SENSOR

VV5404 & VV6404
4.3.1 Blank lines
In addition to padding between data lines, actual blank data lines may appear in the positions indicated above. These
lines begin with start-of-blank-line embedded control sequences and are constructed identically to active video lines
except that they will contain only blank bytes (07_H).
4.3.2 Black line timing
The black lines (which are used for black level calibration) are identical in structure to valid video lines except that
they begin with a start-of-black line sequence and contain either information from the sensor ‘black lines’ or blank
bytes (07_H).
4.3.3 Valid video line timing
All valid video data is contained on active video lines. The pixel data appears as a continuous stream of bytes within
the active lines. The pixel data may be separated from the line header and end-of-line control sequence by a number
of ‘blank’ bytes (07_H), e.g. when the border lines and pixels are disabled 07_H is output in place of pixels 0, 1, 354 and
355.
4.3.4 Start of frame line timing
The start of frame line which begins each video field contains no video data but instead contains the contents of all
the serial interface registers. This information follows the start-of-line header immediately and is terminated by an
end-of-line control sequence. To ensure that no escape/sync characters appear in the sensor status/configuration
information the code 07_H is output after each serial interface value. Thus it takes 256 pixel clock periods (512 system
clocks) to output all 128 of the serial interface registers. The remainder of the 356 pixel periods of the video portion
of the line is padded out using 07_H values. The first two pixel locations are also padded with 07_H characters (Figure 8)
If a serial interface register location is unused then 07_H is output. The read-out order of the registers is independent
of whether the pixel read-out order is shuffled or un-shuffled.
4.3.5 End of frame line timing
The end of frame line which begins each video field contains no video data. Its sole purpose is to indicate the end of
a frame.
4.4 Detection of sensor using data bus state
The video processor device must have internal pull-down terminations on the data bus. On power-up a sensor will
pull all data lines high for a guaranteed period. This scheme allows the presence of a sensor on the interface to be
detected by the video processor on power-up, and the connection of a sensor to an already power-up interface (a
‘hot’ connection).
The absence of a sensor is detected by the video processor seeing more than 32 consecutive nibbles of 0_H on the
data bus. On detecting the absence of a sensor, CKI, should be disabled (held low).
The presence of a sensor is detected by the video processor seeing more than 32 consecutive nibbles of F_H on the
data bus. On detecting the presence of a sensor, CKI, should be enabled.
4.5 Resetting the Sensor Via the Serial Interface
Bit 2 of setup register 0 allows the VV6404 sensor to be reset to its power-on state via the 2-wire serial interface.
Setting this “Soft Reset” bit causes all of the serial interface registers including the “Soft Reset” bit to be reset to their
default values. This “Soft Reset” leaves the sensor in low-power mode and thus an “Exit Low-Power Mode” command
(Section 4.6.2) must be issued via the serial interface before the sensor will start to generate video data (Figure 9).
4.6 Power-up, Low-power and Sleep modes
To clarify the state of the interface on power-up and in the case of a ‘hot’ connection of the interface cable the power-
up state of the bus is defined below.
CD5404-6404F-A
14/54