Rtsi Trigger Bus - National Instruments NI 783xR User Manual

Chapter 2 Hardware Overview of the NI 783xR
Digital Lines
Connector 0, DIO<0..7>;
Connector 1, DIO<0..27>;
Connector 2, DIO<0..27>
Connector 0, DIO<8..15>;
Connector 1, DIO<28..39>;
Connector 2, DIO<28..39>

RTSI Trigger Bus

NI 783xR User Manual
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.
Table 2-4. DIO Signal Guidelines for the NI 783xR
SH68-C68-S Shielded Cable
Signal Pairing
DIO line paired with power
or ground
DIO line paired with another
DIO line
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.
All types—high-frequency or
low-frequency signals,
edge-sensitive or
non-edge-sensitive signals
Static signals or
non-edge-sensitive,
low-frequency signals
2-18
Recommended Types
of Digital Signals
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