National Instruments 3.21E+04 Manual De Usuario

Chapter 4     Signal Connections

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 National Instruments Corporation

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AT-MIO/AI E Series User Manual

external TRIG1 source and an external CONVERT* source to two of 
the AT E Series board PFI pins.

Figure 4-12.  Timing I/O Connections

There are a total of 13 internal timing signals that you can externally 
control from the PFI pins.  The source for each of these signals is 
software selectable from any of the PFIs when you want external 
control.  This flexible routing scheme reduces the need to change the 
physical wiring to the board I/O connector for different applications 
requiring alternative wiring.

You can individually enable each of the PFI pins to output a specific 
internal timing signal.  For example, if you need the CONVERT* signal 
as an output on the I/O connector, software can turn on the output driver 
for the PFI2/CONVERT* pin.  You must be careful not to drive a PFI 
signal externally when it is configured as an output.

As an input, you can individually configure each PFI for edge or level 
detection and for polarity selection, as well.  You can use the polarity 
selection for any of the 13 timing signals, but the edge or level detection 
will depend upon the particular timing signal being controlled.  The 

TRIG1

Source

DGND

PFI0/TRIG1

PFI2/CONVERT*

CONVERT*

Source

I/O Connector

AT E Series Board