Description of the data path
GUPPY Technical Manual
V4.0.1
85
Loading a LUT into the camera
Loading the LUT is carried out through the data exchange buffer called
GPDATA_BUFFER. As this buffer can hold a maximum of 2 kB, and a complete
LUT at 1024 x 8 bit is 1 kB, programming can take place in a one block write
step. The flow diagram below shows the sequence required to load data into
the camera.
Note
L
•
The input value is the 10-bit value from the digitizer.
The gamma LUT of the CCD models outputs the most
significant 8 bit as shown above.
•
As gamma correction for the CCD models is also imple-
mented via the look-up table, it is not possible to use a
different LUT when gamma correction is enabled.
•
With all CCD models, the user LUT will be overridden
when gamma is enabled.
•
CMOS models have the gamma function built in the sen-
sor, so that it will not be overridden.
•
LUT content is volatile.
Figure 38: Loading a LUT