Chapter 3 Hardware OverviewPCI E Series User Manual3-14 ©National Instruments CorporationAnalog Trigger♦ PCI-MIO-16E-1, PCI-MIO-16E-4, PCI-MIO-16XE-10, PCI-6031E,PCI-6032E, PCI-6033E, and PCI-6071EIn addition to supporting internal software triggering and externaldigital triggering to initiate a data acquisition sequence, these boardsalso support analog triggering. You can configure the analog triggercircuitry to accept either a direct analog input from the PFI0/TRIG1 pinon the I/O connector or a postgain signal from the output of the PGIA,as shown in Figure 3-6. The trigger-level range for the direct analogchannel is ±10 V in 78 mV steps for the PCI-MIO-16E-1,PCI-MIO-16E-4, and PCI-6071E, and ±10 V in 4.9 mV steps for thePCI-MIO-16XE-10, PCI-6031E, PCI-6032E, and PCI-6033E. Therange for the post-PGIA trigger selection is simply the full-scale rangeof the selected channel, and the resolution is that range divided by 256for the PCI-MIO-16E-1, PCI-MIO-16E-4, and PCI-6071E and dividedby 4,096 for the PCI-MIO-16XE-10, PCI-6031E, PCI-6032E, andPCI-6033E.Note: The PFI0/TRIG1 pin is an analog input when configured as an analogtrigger. Therefore, it is susceptible to crosstalk from adjacent pins, whichcan result in false triggering when the pin is left unconnected. To avoidfalse triggering, make sure this pin is connected to a low-impedance signalsource (less than 1 kΩ source impedance) if you plan to enable this inputvia software.Figure 3-6. Analog Trigger Block DiagramAnalogInputChannelsPFI0/TRIG1PGIA+-ADCDAQ-STCAnalogTriggerCircuitMux
