The SignalBus Display is only a quick check for the mentioned signals.
There is no guaranty that these signals change their level in the right time scedule.
To be sure that the time "Ablauf" is correct, measure this signals with an oscilloscope.
The measuing points you should connect your probes are mentioned below:
EN_X/= enable X-ray, system level
CTRL_X/= control X-ray request command, system level
RQ_SN_X/= request synchronization of X-ray
X_ACT/= signal bus X-ray active