National Instruments SCXI -1125 用户手册

time. For continuous acquisition, you must use a while loop around the 
acquisition components even if you configured the task for continuous 
acquisition using MAX or the DAQ Assistant. For continuous and buffered 
acquisitions, you can set the acquisition rate and the number of samples to 
read in the DAQ Assistant or programmatically in your application. By 
default, the clock settings are automatically set by an internal clock based 
on the requested sample rate. You also can select advanced features such as 
clock settings that specify an external clock source, internal routing of the 
clock source, or select the active edge of the clock signal.

All ADEs used to configure the SCXI-1125 access an underlying set of 
NI-DAQmx properties. Table 5-3 shows some of these properties. You can 
use Table 5-3 to determine what kind of properties you need to set to 
configure the module for your application. For a complete list of 
NI-DAQmx properties, refer to your ADE help file.

You cannot adjust some properties while a task is running. For these properties, you 

must stop the task, make the adjustment, and re-start the application. Figure 5-1 assumes 
all properties are configured before the task is started.

This is not a complete list of NI-DAQmx properties and does not include every 

property you may need to configure your application. It is a representative sample of 
important properties to configure for measurements. For a complete list of NI-DAQmx 
properties and more information about NI-DAQmx properties, refer to your ADE help file.

Table 5-3.  NI-DAQmx Properties 

AI.Max

Specifies the upper limit of the 
input range.

AI.Min

Specifies the lower limit of the 
input range.

AI.Lowpass.CutoffFreq

Specifies in hertz the 
frequency corresponding to the 
–3 dB cutoff of the filter. You 
can specify 4.0 or 10000.