National Instruments 3.21E+04 사용자 설명서

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Chapter 4     Signal Connections
AT-MIO/AI E Series User Manual
4-30
 National Instruments Corporation
Power Connections
Two pins on the I/0 connector supply +5 V from the PC power supply 
via a self-resetting fuse.  The fuse will reset automatically within a few 
seconds after the overcurrent condition is removed.  These pins are 
referenced to DGND and can be used to power external digital circuitry.
Power rating
+4.65 VDC to +5.25 VDC at 1 A combined total
 for both pins
Warning: Under no circumstances should you connect these +5 V power pins directly 
to analog or digital ground or to any other voltage source on the 
AT E Series board or any other device.  Doing so can damage the 
AT E Series board and the PC.  National Instruments is 
NOT
 liable for 
damages resulting from such a connection.
Timing Connections
Warning: Exceeding the maximum input voltage ratings, which are listed in 
Tables 4-1 through 4-4, can damage the AT E Series board and the PC. 
National Instruments is 
NOT
 liable for any damages resulting from such 
signal connections.
All external control over the timing of your AT E Series board is routed 
through the 10 programmable function inputs labeled PFI0 through 
PFI9.  These signals are explained in detail in the next section, 
Programmable Function Input Connections.  These PFIs are 
bidirectional; as outputs they are not programmable and reflect the state 
of many data acquisition, waveform generation, and general-purpose 
timing signals.  There are five other dedicated outputs for the remainder 
of the timing signals.  As inputs, the PFI signals are programmable and 
can control any data acquisition, waveform generation, and 
general-purpose timing signals.
The data acquisition signals are explained in the Data Acquisition 
Timing Connections 
section later in this chapter.  The waveform 
generation signals are explained in the Waveform Generation Timing 
Connections 
section later in this chapter.  The general-purpose timing 
signals are explained in the General-Purpose Timing Signal Connections 
section later in this chapter.
All digital timing connections are referenced to DGND.  This reference 
is demonstrated in Figure 4-12, which shows how to connect an