National Instruments NI 6013, Руководство пользователя

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Chapter 4 Connecting Signals
© National Instruments Corporation 4-19 NI 6013/6014 User Manual
Figure 4-9 shows DIO<0..3> configured for digital input and DIO<4..7>
configured for digital output. Digital input applications include receiving
TTL signals and sensing external device states, such as the switch state
shown in the Figure 4-9. Digital output applications include sending TTL
signals and driving external devices, such as the LED shown in Figure 4-9.
Power Connections
Two pins on the I/O connector 5 V from the computer power
supply using a self-resetting fuse. The fuse resets 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.
The power rating is +4.65 to +5.25 VDC at 1 A.
Caution Do not connect these +5 V power pins directly to analog or digital ground or to
any other voltage source on the NI 6013/6014 or any other device. Doing so can damage
the NI 6013/6014 and the computer. NI is
not liable for damage resulting from such
a connection.
Connecting Timing Signals
Caution Exceeding the maximum input voltage ratings, which are listed in Table 4-3, can
damage the device and the computer. NI is not liable for any damage resulting from such
signal connections.
All external control over the timing of the device is routed through the
10 PFIs labeled PFI<0..9>. These signals are explained in detail in the
Programmable Function Input Connections section. These PFIs are
bidirectional; as outputs they are not programmable and reflect the state
of many DAQ, 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 DAQ, waveform generation, and general-purpose timing signals.
The DAQ signals are explained in the DAQ Timing Connections section.
The Waveform Generation Timing Connections section explains the
waveform generation signals, and the General-Purpose Timing Signal
Connections section explains the general-purpose timing signals.