The characteristic curve scaling is used to scale the recorded signals in real time on the measurement card. The scaling takes place directly on the signal processor of the measurement card and therefore does not require any computing power on the PC side. The characteristic curve scaling on the measurement cards of the Multichoice PCI and USB series is only available with the “Online linearization” option enabled. The characteristic curve scaling is set in the measuring program via settings of the analog acquisition block. This transfers a list of the support points to the DSP, which describe the signal scaling. The scaling takes place on the entire set voltage range. The definition of the support points takes place in a separate text file in which the corner points are simply stored line by line.
To enable scaling, (2 exp. X) +1 corner points are required, whereby 0 If fewer coefficients are selected than are available in the file, the following values ​​are ignored.
The coefficient files can be created very comfortably, for example with Excel, and saved as a text file. The point “.” Is used as the decimal separator. used!

An example of a coefficient file:

0.0
1.0
5.0
6th
10

The number of points given is 5 ((2 exp. 2) +1)

In the example, when the input voltage range is set from -10 to +10, the recorded measured values ​​are scaled as follows according to the definition of the output range:

-10 to -5V -> 0 to 1V
-5 to 0V -> 1 to 5V
0 to 5V -> 5 to 6V
5 to 10V -> 6 to 10V

Triggers are conditions that are monitored during the runtime of a measurement. These conditions relate to the measured values ​​that have just been recorded; in the case of individual value processing, this monitoring takes place within a specified response time depending on the sampling rate.

Up to 10,000 times faster than software
triggers on the PC If trigger conditions are implemented by measuring programs on the PC system, the response times to a trigger that has occurred are well beyond the millisecond range, since the measured value is first recorded, transferred to the PC system, processed and the control commands sent back to the measurement hardware and output there. However, if this trigger is executed on the signal processor, it is processed immediately after the measurement value has been recorded before it is transmitted to the PC. The reactions can be started directly on the measurement card without the PC having to control it separately. The response times are in the nanosecond range without the PC system being burdened with additional controls.

Flexible combinations possible
By using triggers during a measurement, it is possible to react to events during a measurement at short notice. The limit or threshold values ​​to be monitored are set before the start of the measurement and can be changed dynamically during the actual measurement. Several trigger conditions can be selected per channel, which can also be linked to one another using Boolean logic.

Control of external events
A trigger event that has occurred can start or stop a measurement, digital outputs can be configured or an analog output is controlled. Optionally, these trigger conditions can also activate or deactivate each other so that a whole network of dynamic triggers is available depending on the course of the measurement. The trigger conditions can be defined in a retriggerable manner, i.e. either deactivate or reactivate after a condition has been fulfilled in order to carry out the same or a changed monitoring.

Versatile trigger types Limit
or threshold value monitoring for edges, limit values ​​or window conditions are available as trigger conditions; the measured values ​​can be offset against the previous values ​​and acted on depending on the slope of the resulting curve (gradient slope), this also within threshold value and window conditions.

Easy to automate
The adjustable actions, which are automatically carried out when an event is fulfilled, allows control or monitoring to be implemented within a guaranteed response time. For example, test bench monitoring with emergency shutdown via the digital outputs is conceivable, which shuts down the test bench quickly and safely if one of the monitored measured variables is exceeded, without external intervention being necessary. Saving the triggered trigger event with the last value is possible without any problems so that the cause of the emergency shutdown is not lost.

Easiest operation
Depending on the measuring program used, the trigger parameters are set simply via the user interface of the card settings. The predefined masks ensure user-friendly and simple operation, so that even complex conditions can be easily configured. Here you will find examples for trigger configurations in DIAdem , DasyLab and LabView .