National Instruments 6008 用户手册

© National Instruments Corporation

When you use a DAC to generate a waveform, you may observe glitches in 
the output signal. These glitches are normal; when a DAQ switches from 
one voltage to another, it produces glitches due to released charges. The 
largest glitches occur when the most significant bit of the DAC code 
changes. You can build a lowpass deglitching filter to remove some of 
these glitches, depending on the frequency and nature of the output signal. 
Refer to 

ni.com/support

 for more information about minimizing 

glitches.

The NI USB-6008/6009 has 12 digital lines, P0.<0..7> and P1.<0..3>, 
which comprise the DIO port. GND is the ground-reference signal for the 
DIO port. You can individually program all lines as inputs or outputs. 

Figure 13 shows P0.<0..7> connected to example signals configured as 
digital inputs and digital outputs. You can configure P1.<0..3> similarly.

Figure 13.  Example of Connecting a Load

1

P0.0 configured as an open collector digital output driving a LED

2

P0.2 configured as a active drive digital output driving a LED

3

P0.4 configured as a digital input receiving a TTL signal from a gated invertor

4

P0.7 configured as a digital input receiving a 0 V or 5 V signal from a switch

+5 V

LED

Switch

I/O Connector

 GND

P0.0
P0.1
P0.2
P0.3
P0.4
P0.5
P0.6
P0.7

+5 V

LED

1

2

3

4

TTL Signal