Cronologic Ndigo5G-10, User Manual

Page: 23 / 54

Trigg
er
Figure 2.23: Gating block logic for the AND connection of two triggers.
2.4.5 Auto Triggering Function Generator
Some applications require periodic or random triggering. Ndigo5G’s function generator provides
this functionality.
The delay between two trigger pulses of this trigger generator is the sum of two components:
A fixed value M and a pseudo random value given by the exponent N.
The period is
T = 1 + M + [1 ... 2
N
] (2.1)
clock cycles with a duration of 3.2 ns per cycle.
This allows to monitor input signals at times the current trigger configuration does not trigger,
e. g. to get base line information in mass spectrometry applications. It can also be used to
determine a suitable threshold level for the trigger by first getting random statistics on the input
signal.
2.4.6 Timestamp Channel
The timestamp channel produces a stream of small packets that denote the time of the trigger
event. An arbitrary set of trigger sources can be selected in the trigger matrix to cause the
creation of a packet.
The packets have a fixed length of 16 bytes. The format is described on page 41 . The length
field of the packet contains a 32 bit pattern that contains the levels of all trigger sources at the
cronologic GmbH & Co. KG 18 Ndigo5G User Guide