National Instruments NI 783xR Manuel D’Utilisation

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Chapter 2
Hardware Overview of the NI 783xR
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signals or non-edge-sensitive, low-frequency digital signals. Examples of 
high-frequency or edge-sensitive signals include clock, trigger, pulse-width 
modulation (PWM), encoder, and counter signals. Examples of static 
signals or non-edge-sensitive, low-frequency signals include LEDs, 
switches, and relays. Table 2-4 summarizes these guidelines.
RTSI Trigger Bus
The NI 783xR can send and receive triggers through the RTSI trigger bus. 
The RTSI bus provides eight shared triggers lines that connect to all the 
devices on the bus. In PXI, the trigger lines are shared between all the PXI 
slots in a bus segment. In PCI, the RTSI bus is implemented through a 
ribbon cable connected to the RTSI connector on each device that needs to 
access the RTSI bus.
You can use the RTSI trigger lines to synchronize the NI 783xR to any other 
device that supports RTSI triggers. On the NI PCI-783xR, the RTSI trigger 
lines are labeled RTSI/TRIG<0..6> and RTSI/OSC. On the NI PXI-783xR, 
the RTSI trigger lines are labeled PXI/TRIG<0..7>. In addition, the 
NI PXI-783xR can use the PXI star trigger line to send or receive triggers 
from a device plugged into Slot 2 of the PXI chassis. The PXI star trigger 
line on the NI PXI-783xR is PXI/STAR.
The NI 783xR can configure each RTSI trigger line either as an input or an 
output signal. Because each trigger line on the RTSI bus is connected in 
parallel to all the other RTSI devices on the bus, only one device should 
drive a particular RTSI trigger line at a time. For example, if one 
NI PXI-783xR is configured to send out a trigger pulse on PXI/TRIG0, 
the remaining devices on that PXI bus segment must have PXI/TRIG0 
configured as an input.
Table 2-4.  DIO Signal Guidelines for the NI 783xR
Digital Lines
SH68-C68-S Shielded Cable 
Signal Pairing
Recommended Types 
of Digital Signals
Connector 0, DIO<0..7>; 
Connector 1, DIO<0..27>; 
Connector 2, DIO<0..27>
DIO line paired with power 
or ground
All types—high-frequency or 
low-frequency signals, 
edge-sensitive or 
non-edge-sensitive signals
Connector 0, DIO<8..15>; 
Connector 1, DIO<28..39>; 
Connector 2, DIO<28..39>
DIO line paired with another 
DIO line
Static signals or 
non-edge-sensitive, 
low-frequency signals