Cronologic Ndigo5G-10, User Manual

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Flashing the values might take up to 10 seconds during which the program might not respond.
Important note : If the application reports a “PLL not locked” error check the cable. If the
recording of histograms does not make progress check the cable. Make sure the cable is properly
terminated at both ends and firmly attached to each card.
2.5.1 Calibration Procedure
1. Make sure the “Automode” is selected.
2. Record the calibration histograms by pressing “Record histograms”. The program will
perform up to 200 measurements of the sync delay. After accumulating some data, the
delay values found are reported in the column “AutoMmt”. The values can be verified by
examining the histogram that was recorded. A board’s histogram should look like the one
shown in Figure
2.25 . During normal operation the delay will be adjusted such that the
data points accumulated roughly coincide with the vertical markers in the upper panel. As
the delay pattern is periodic valid delay values are between 0 and 31. Thus, the delay value
found by the auto measurement should correspond to the distance between the vertical
markers and accumulated data points. Hint: When moving the mouse pointer across the
histogram the delay value of the current location is displayed.
3. After stopping the data acquisition, by pressing “Record Histograms” again or waiting
for 200 measurements to complete, the delay values of the auto measurement need to be
copied to the columns “Delay M” or “Delay S” depending on the corresponding board
being a master or a slave. The correct field to copy the value to is highlighted in green.
4. You may record a new dataset as a crosscheck that the delay is now set to an appro-
priate value. By disabling “Automode” the new delay values are used. Press “Record
Histograms” in order to start the data acquisition. After some time the histogram should
look similar to the one in Figure
2.26 .
5. The delay values for all boards in a set needs to be found. For the case a board acts as
a master, the value “Delay M” needs to be adjusted, in case it is a slave, the “Delay S”
parameter needs to be changed. In order to find the master-case delay values for all boards,
the calibration procedure needs to be performed with every board acting as a master once.
After changing the master board, the slave values of the other boards don’t need to be
readjusted. Only Ndigo5G boards may be set as masters. Therefore, a Ndigo250M board
only needs to be calibrated as a slave.
6. After finding all delay values, write the values to the on-board flash PROMs by pressing
“Flash All!”.
cronologic GmbH & Co. KG 20 Ndigo5G User Guide