Photon Focus OEM-D1024E, Руководство пользователя

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Frame time Frame time is the inverse of frame rate.
Exposure time Period during which the pixels are integrating the incoming light.
PCLK Pixel clock on parallel data interface.
SHUTTER
Internal signal, shown only for clarity. Is ’high’ during the exposure
time.
FVAL
(Frame Valid) Is ’high’ while the data of one whole frame are transferred.
LVAL (Line Valid) Is ’high’ while the data of one line are transferred. Example: To transfer
an image with 640 x 480 pixels, there are 480
LVAL
within one
FVAL
active high period. One
LVAL
lasts 640 pixel clock cycles.
DVAL (Data Valid) Is ’high’ while data are valid.
DATA Transferred pixel values. Example: For a 100 x 100 pixel image, there
are 100 values transferred within one
LVAL active high period, or
100*100 values within one FVAL period.
Line pause Delay before the first line and after every following line when reading
out the image data.
Table 5.6: Explanation of control and data signals used in the timing diagram
These terms will be used also in the timing diagrams of Section 5.4.
5.3.2 Constant Frame Rate Mode (CFR)
When the camera module is in constant frame rate mode, the frame rate can be varied up to
the maximum frame rate. Thus, fewer images can be acquired than determined by the frame
time. When constant frame rate is switched off, the camera module outputs images with
maximum speed, depending on the exposure time and the read-out time. The frame rate
depends directly on the exposure time.
Constant Frame Rate mode is not available together with external trigger mode.
5.3 Read-out Timing 53