Cronologic Ndigo5G-10, Руководство пользователя

Страница: 20 / 54

2.4.4 Gating Blocks
Trigg
er
Figure 2.20: Gating Blocks: Each gating block can use an arbitrary combination of inputs to
trigger its state machine. The outputs can be individually inverted and routed to
the AND-gate feeding the trigger blocks.
To decrease the amount of data transmitted to the PC, Ndigo5G includes 4 independent gate
and delay units. A gate and delay unit creates a gate window starting at a specified time after
a trigger, closing the window at gate stop. Both timing values — gate start and gate stop —
must be set as multiples of 3.2ns.
Trigger blocks can use the gate signal to suppress data acquisition: Only data that fulfills
zero suppression specifications occurring in an active gate window is written to the PC.
As input, any trigger from the 4 trigger blocks, the GATE and Trigger inputs, a trigger from
a connected board and the function generator can be used.
The retrigger feature will create a new gate if a trigger occurs during an active gate window.
The gate signal can be inverted, causing an active gate to close for a time defined by the user.
The parameters of a gating block are set in Structure ndigo gating block described on page
36 .
Figure 2.21 shows the functionality of the gate timing and delay unit. Active gate time is
marked in green.
cronologic GmbH & Co. KG 15 Ndigo5G User Guide