Cronologic Ndigo5G-10, User Manual

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time of the trigger event except for the period monitor. Only one packet is created, no matter
how many trigger sources caused the timestamp channel to trigger.
2.4.7 Data Lookup Table
In some applications it might be useful to modify the ADC sample data by a user defined function
f ( x ). In this case the onboard FPGA is able to perform this task such that the the data stream
consists of data words f ( sample ) instead of sample . The function f(x) is applied using a 1024
word lookup table (LUT) which needs to be provided by the user. This is done by defining
the corresponding function as a custom lut-member of the ndigo configuration structure. Please
feel free to contact cronologic if you plan the use this feature. The onboard INL correction is
applied prior to mapping the LUT values.
2.5 Multiple Ndigo boards synchronization
Using several Ndigo devices in applications that use more channels than a single board can
provide requires synchronized operation. To ensure exact synchronization, a delay parameter
needs to be set for each board. This parameter might change in case boards are swapped, added
or removed and in some cases might change after a firmware update.
The calibration tool “MultiboardCalibration.exe” is available after installing the Ndigo device
driver. It is used to find appropriate delay values for each board in a given board setup. After
starting, the application lists all Ndigo boards found (Figure
2.24 ).
Figure 2.24: Main window of the multiple boards sync calibration tool
A board’s appropriate delay depends on whether it operates in master or slave mode. The
respective values can be set in the column “Delay M” (for master boards) and “Delay S” (for
slave boards). The designated master board can be selected in the column “Master”. The
calibration procedure creates a histogram for each board displaying the current delay between
the boards. The histogram can be viewed by clicking on “Show!”. When the appropriate delay
values are found they can be stored in the on-board flash PROM by clicking “Do it!” separately
for each board. Clicking “Flash All!” will write the values to all boards at once. Please note:
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