National Instruments NI cRIO-905x Series User manual

USER MANUAL
NI cRIO-905x
Embedded CompactRIO Controller with Real-Time Processor and
Reconfigurable FPGA
This document describes the features of the cRIO-905x and contains information about
mounting and operating the device.
In this document, the NI cRIO-9053, NI cRIO-9054, NI cRIO-9056, NI cRIO-9057 are
referred to collectively as cRIO-905x.

Contents
Configuring the cRIO-905x...................................................................................................... 2
Connecting the cRIO-905x to the Host Computer Using USB........................................ 3
Connecting the cRIO-905x to the Host Computer or Network Using Ethernet............... 4
Configuring Startup Options.............................................................................................4
cRIO-905x Features.................................................................................................................. 6
Ports and Connectors........................................................................................................ 6
Buttons............................................................................................................................ 10
LEDs................................................................................................................................11
Chassis Grounding Screw............................................................................................... 14
Internal Real-Time Clock................................................................................................14
Digital Routing................................................................................................................14
Clock Routing................................................................................................................. 15
Synchronization Across a Network.................................................................................16
Battery.............................................................................................................................18
File System......................................................................................................................18
Mounting the Controller..........................................................................................................19
Alternative Mounting Configurations.............................................................................20
Mounting Requirements..................................................................................................20
Dimensions......................................................................................................................21
Front Mounting on a Flat Surface................................................................................... 23
Rear Mounting on a Flat Surface.................................................................................... 25
Mounting the Controller on a Panel ...............................................................................27
Mounting on a DIN Rail ................................................................................................ 31
Mounting on a Rack........................................................................................................33
Mounting the Device on a Desktop.................................................................................33
Choosing Your Programming Mode....................................................................................... 37
Analog Input with NI-DAQmx....................................................................................... 38
Analog Output with NI-DAQmx.................................................................................... 44
Digital Input/Output with NI-DAQmx........................................................................... 50
PFI with NI-DAQmx...................................................................................................... 62
Counters with NI-DAQmx..............................................................................................63
Counter Input Applications.............................................................................................68
Counter Output Applications.......................................................................................... 87
Counter Timing Signals.................................................................................................. 95
Worldwide Support and Services.......................................................................................... 100
Configuring the cRIO-905x
You can connect the cRIO-905x to a host computer or network and configure the startup
options using the USB 2.0 Type-C Device Port with Console Out or the RJ-45 Gigabit
Ethernet port 0.
Tip Refer to the NI cRIO-905x Getting Started Guide for basic configuration
instructions and information about connecting to a host computer using the USB 2.0
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Type-C Device Port with Console Out. NI recommends using the USB 2.0 Type-C
Device Port with Console Out for configuration, debugging, and maintenance.
Connecting the cRIO-905xto the Host Computer Using
USB
Complete the following steps to connect the cRIO-905x to the host computer using the USB
2.0 Type-C Device Port with Console Out.
1. Power on the host computer.
2. Connect the cRIO-905x to the host computer using the USB Type C to Type A cable
(included in kit), inserting the USB Type-C connector into the USB 2.0 Type-C Device
Port with Console Out.
3. Connect the other end of the USB cable (Type-A) to the host computer.
Note The device driver software automatically detects the cRIO-905x. If the
device driver software does not detect the cRIO-905x, verify that you installed
the appropriate NI software in the correct order on the host computer as
described in Installing Software on the Host Computer in the NI cRIO-905x
Getting Started Guide.
4. Select Configure and install software to this device.
NI cRIO-905x User Manual | © National Instruments | 3

Connecting the cRIO-905x to the Host Computer or
Network Using Ethernet
Complete the following steps to connect the cRIO-905x to a host computer or Ethernet
network using the RJ-45 Gigabit Ethernet port 0. NI recommends using the RJ-45 Gigabit
Ethernet port 0 for communication with deployed systems.
Note If your controller has the RJ-45 Gigabit Ethernet port 1, you can configure
that port in Measurement & Automation Explorer (MAX) under the Network
Settings tab.
1. Power on the host computer or Ethernet hub.
2. Connect the RJ-45 Gigabit Ethernet port 0 on the cRIO-905x to the host computer or
Ethernet hub using a standard Category 5 (CAT-5) or better shielded, twisted-pair
Ethernet cable.
Notice To prevent data loss and to maintain the integrity of your Ethernet
installation, do not use a cable longer than 100 m (328 ft).
The cRIO-905x attempts to initiate a DHCP network connection the first time you
connect using Ethernet. The cRIO-905x connects to the network with a link-local IP
address with the form 169.254.x.x if it is unable to initiate a DHCP connection.
Finding the cRIO-905x on the Network (DHCP)
Complete the following steps to find the cRIO-905x on a network using DHCP.
1. Disable secondary network interfaces on the host computer, such as a wireless access
card on a laptop.
2. Ensure that any anti-virus and firewall software running on the host computer allows
connections to the host computer.
Note MAX uses UDP on port 44525. Refer to the documentation of your
firewall software for information about configuring the firewall to allow
communication through this port.
3. Launch MAX on the host computer.
4. Expand Remote Systems in the configuration tree and locate your system.
Tip MAX lists the system under the model number followed by the serial
number, such as NI-cRIO-905x-1856AAA.
Tip If you do not see the cRIO-905x under Remote Systems, use the
Troubleshoot Remote System Discovery utility to walk through
troubleshooting steps.
Configuring Startup Options
Complete the following steps to configure the cRIO-905x startup options in MAX.
1. In MAX, expand your system under Remote Systems.
2. Select the Startup Settings tab to configure the startup settings.
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cRIO-905xStartup Options
You can configure the following cRIO-905x startup options.
Table 1. cRIO-905xStartup Options
Startup Option Description
Force Safe Mode Rebooting the cRIO-905x with this setting on starts the cRIO-905x
without launching LabVIEW Real-Time or any startup applications. In
safe mode, the cRIO-905x launches only the services necessary for
updating configuration and installing software.
Enable Console
Out
Rebooting the cRIO-905x with this setting on redirects the console
output to the USB 2.0 Type-C Device Port with Console Out. You can
use a serial-port terminal program to read the IP address and firmware
version of the cRIO-905x. Make sure that the serial-port terminal
program is configured to the following settings:
• 115,200 bits per second
• Eight data bits
• No parity
• One stop bit
• No flow control
Disable RT
Startup App
Rebooting the cRIO-905x with this setting on prevents any LabVIEW
startup applications from running.
Disable FPGA
Startup App
Rebooting the cRIO-905x with this setting on prevents autoloading of
any FPGA application.
Enable Secure
Shell (SSH)
Logins
Rebooting the cRIO-905x with this setting on starts sshd on the
cRIO-905x. Starting sshd enables logins over SSH, an encrypted
communication protocol.
Note Visit ni.com/info and enter the Info Code openssh
for more information about SSH.
LabVIEW Project
Access
Rebooting the cRIO-905x with this setting on enables you to add the
target to a LabVIEW project.
NI cRIO-905x User Manual | © National Instruments | 5

cRIO-905x Features
Ports and Connectors
Figure 1. cRIO-905xPorts and Connectors
1
2
3
4
56
1. USB 2.0 Type-C Device Port with Console Out
2. USB 3.1 Type-C Host Port
3. PFI 0
4. Power Connector
5. SD Association MicroSD Card Removable
Storage
6. RJ-45 Gigabit Ethernet Ports (one or two,
depending on the model)
USB 2.0 Type-C Device Port with Console Out
When operating a device, use this port to connect the cRIO-905x to a host PC. The USB
device functionality provides an alternate method to connect the controller to a host PC for
configuration, application deployment, debugging, and maintenance.
Console Out over USB requires a virtual COM port driver on the host PC. This driver installs
with CompactRIO 18.1 or later.
You must enable Console Out on the cRIO-905x in Measurement & Automation Explorer
(MAX) or by booting the controller into Safe Mode.
Note This port cannot be accessed by the user application when the Console Out
startup option is enabled.
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USB 3.1 Type-C Host Port
The USB host port on the cRIO-905x support common USB mass-storage devices such as
USB Flash drives, USB-to-IDE adapters, keyboards, mice, and USB cameras.
The following NI USB Type-C adapters are available for the cRIO-905x.
Table 2. NI USB Type-C Adapters for cRIO-905x
Cable Length Part Number
USB Cable with Retention, Type-C Male to Type-A Female, USB
3.1, 3A
0.5 m 143555-0R5
The following NI cables with retention are available for use with the cRIO-905x.
Table 3. NI USB Cables with Retention
Cable Length Part Number
USB Cable with Retention, Type-C Male to Type-C Male, USB 3.1,
3A
0.3 m 143556-0R3
1 m 143556-01
2 m 143556-02
PFI 0
The Programmable Function Interface (PFI) terminal is a SMB connector. You can configure
the PFI terminal as a timing input or timing output signal for AI, AO, DI, DO, or counter/timer
functions.
Note The PFI 0 terminal can only be used while the module is in the Real Time
programmatic mode. For more information about programming modes, refer to
Choosing Your Programming Mode.
Power Connector
The cRIO-905x has a power connector to which you can connect a power supply.
Table 4. Power Connector Pinout
Pinout Pin Description
V
C
V Power input
C Common
NI cRIO-905x User Manual | © National Instruments | 7

The cRIO-905x has reverse-voltage protection.
The following NI power supplies and accessories are available for use with the cRIO-905x.
Table 5. Power Supplies
Accessory Part Number
NI PS-10 Desktop Power Supply, 24 V DC, 5 A, 100-120/200-240 V AC
Input
782698-01
NI PS-14 Industrial Power Supply, 24 to 28 V DC, 3.3 A, 100-240 V AC
Input
783167-01
NI PS-15 Industrial Power Supply, 24 to 28 V DC, 5 A, 100/230 V AC Input 781093-01
NI PS-16 Industrial Power Supply, 24 to 28 V DC, 10 A, 115/230 V AC Input 781094-01
NI PS-17 Industrial Power Supply, 24 to 28 V DC, 20 A, 85-276 V AC Input 781095-01
Table 6. Power Accessories
Accessory Part Number
2-Position Screw Terminal Power Connector for cRIO-905x (Qty 4) 786902-01
NI 9971 Backshell for 2-Position Connector Block (Qty 4) 196375-01
MicroSD Card Removable Storage
The cRIO-905x has a microSD card slot that reads from and writes to microSD cards. The slot
supports microSD card interface speeds up to UHS-I DDR50.
Notice Using microSD cards that are not approved by NI might invalidate
specifications and result in unreliable performance.
The following accessories are available for use with the cRIO-905x.
Table 7. MicroSD Storage Accessories
Accessory Capacity Part Number
Industrial microSD card, -40 °C to 85 °C, UHS-I 16 GB 786913-01
MicroSD card slot cover (x3) — 786901-01
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MicroSD Card Slot Cover
You must use the microSD card slot cover to protect the microSD card in hazardous locations.
Do not remove a microSD card while the SD IN USE LED is flashing or solid because file
corruption may result.
Note Screw the slot cover closed completely. Tighten the captive screws to a
maximum torque of 0.75 N · m (6.7 lb · in.) using a #1 Phillips screwdriver. Do not
overtighten.
RJ-45 Gigabit Ethernet Port
The cRIO-905x will have one or two tri-speed RJ-45 Gigabit Ethernet ports. By default, the
Ethernet port is enabled and configured to obtain an IP address automatically. The Ethernet
port can be configured in MAX.
Table 8. RJ-45 Gigabit Ethernet Port Pinout
Fast Ethernet Signal Gigabit Ethernet Signal Pin Pinout
TX+ TX_A+ 1
1
2
3
4
5
6
7
8
TX- TX_A- 2
RX+ RX_B+ 3
No Connect TX_C+ 4
No Connect TX_C- 5
RX- RX_B- 6
No Connect RX_D+ 7
No Connect RX_D- 8
Note The Ethernet port performs automatic crossover configuration so you do not
need to use a crossover cable to connect to a host computer.
The following NI Ethernet cables are available for use with the cRIO-905x.
Table 9. RJ-45 Gigabit Ethernet Cables
Cables Length Part Number
CAT-5E Ethernet Cable, shielded
2 m 151733-02
5 m 151733-05
10 m 151733-10
NI cRIO-905x User Manual | © National Instruments | 9

Buttons
Figure 2. cRIO-905xButtons
1 2 3 4 5 6 7 8
1
2
1. RESET Button
2. CMOS Reset Button
RESET Button
Press the RESET button to reset the processor in the same manner as cycling power.
Figure 3. Reset Button Behavior
Press and hold RESET button for ≥5 s
Press and hold RESET button for < 5 s
Run Mode
Safe Mode
Press and hold RESET button for < 5 s
Press and hold RESET button for ≥5 s
Press and hold
RESET button for ≥5 s
Press and hold
RESET button for < 5 s
• Console Out enabled
• Network settings reset
• RT Startup App disabled
• FPGA Startup App disabled
• Console Out enabled
• RT Startup App disabled
• FPGA Startup App disabled
Safe Mode
For more information about using the RESET button for network troubleshooting, see
Troubleshooting Network Connectivity.
Troubleshooting Network Connectivity
You can use the RESET button to troubleshoot network connectivity.
Complete the following steps to reset the network adapters to default settings.
1. Hold the RESET button for 5 seconds, and then release it to boot the controller in safe
mode and enable Console Out.
2. Hold the RESET button again for 5 seconds to boot the controller into safe mode, enable
Console Out, and reset network adapters to default settings.
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CMOS Reset Button
The cRIO-905x has a CMOS reset button that you can use to reset the CMOS and the BIOS.
LEDs
Figure 4. cRIO-905xFront Panel LEDs
12
34
5
6
1. POWER LED
2. STATUS LED
3. SD IN USE LED
4. USER1 LED
5. USER FPGA1 LED
6. Gigabit Ethernet LEDs
POWER LED Indicators
Table 10. POWER LED Indicators
LED Pattern Indication
Solid The cRIO-905x is powered on.
Off The cRIO-905x is powered off.
NI cRIO-905x User Manual | © National Instruments | 11

STATUS LED Indicators
Table 11. STATUS LED Indicators
LED Pattern Indication
Blinks twice and
pauses
The cRIO-905x is in safe mode. Software is not installed, which is the
factory default state, or software has been improperly installed on the
cRIO-905x. An error can occur when an attempt to upgrade the
software is interrupted. Reinstall software on the cRIO-905x. Refer to
the Measurement & Automation Explorer (MAX) Help for information
about installing software on the cRIO-905x.
Blinks three times
and pauses
The cRIO-905x is in user-directed safe mode, or the cRIO-905x is in
install mode to indicate that software is currently being installed. This
pattern may also indicate that the user has forced the cRIO-905x to
boot into safe mode by pressing the reset button for longer than five
seconds or by enabling safe mode in MAX. Refer to the Measurement
& Automation Explorer (MAX) Help for information about safe mode.
Blinks four times
and pauses
The cRIO-905x is in safe mode. The software has crashed twice
without rebooting or cycling power between crashes.
Continuously blinks The cRIO-905x has not booted into NI Linux Real-Time. The
cRIO-905x either booted into an unsupported operating system, was
interrupted during the boot process, or detected an unrecoverable
software error. If the problem persists, contact NI for support.
On momentarily The cRIO-905x is booting. No action required.
Off The cRIO-905x is in run mode. Software is installed and the operating
system is running.
User LEDs
You can define the behavior of the USER1 LED and the USER FPGA1 LED to meet the needs
of your application.
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Table 12. User LEDs
LED LED Color Description
USER1 Green Use LabVIEW Real-Time to define the USER1 LED with the
RT LEDs VI. For more information about the RT LEDs VI, refer
to the LabVIEW Help.
USER
FPGA1
Green Use the LabVIEW FPGA Module and NI-RIO Device Drivers
software to define the USER FPGA1 LED. Use the USER
FPGA1 LED to help debug your application or retrieve
application status. Refer to the LabVIEW Help for information
about programming this LED.
SD IN USE LED Indicators
Table 13. SD IN USE LED Indicators
LED Pattern Indication
Solid A microSD card is present and mounted.
Off No microSD card is present.
Ethernet LED Indicators
Table 14. Ethernet LED Indicators
LED LED Color LED Pattern Indication
ACT/LINK — Off LAN link not established
Green Solid LAN link established
Flashing Activity on LAN
10/100/1000 Yellow Solid 1,000 Mb/s data rate selected
Green Solid 100 Mb/s data rate selected
— Off 10 Mb/s data rate selected
NI cRIO-905x User Manual | © National Instruments | 13

Chassis Grounding Screw
Figure 5. cRIO-905xChassis Grounding Screw
1
1. Chassis Grounding Screw
Note For information about grounding the cRIO-905x, see Grounding the
Controller in the NI cRIO-905x Getting Started Guide.
Note For more information about ground connections, visit ni.com/info and enter
the Info Code emcground.
Internal Real-Time Clock
The cRIO-905x contains an internal real-time clock that maintains system time when the
cRIO-905x is powered off. The system clock of the cRIO-905x is synchronized with the
internal real-time clock at startup. You can set the real-time clock using the BIOS setup utility
or MAX, or you can set the real-time clock programmatically using LabVIEW.
Refer to the model specifications on ni.com/manuals for the real-time clock accuracy
specifications.
Digital Routing
The digital routing circuitry of the cRIO-905x manages the flow of data between the bus
interface and the acquisition and generation sub-systems when programming C Series modules
in Real-Time (NI-DAQmx) mode. The subsystems include analog input, analog output, digital
14 | ni.com | NI cRIO-905x User Manual

I/O, and counters. The digital routing circuitry uses FIFOs (if present) in each sub-system to
ensure efficient data movement.
Note When programming C Series modules in FPGA mode, the flow of data
between the modules and the bus interface is programmed using LabVIEW FPGA.
The digital routing circuitry also routes timing and control signals. The acquisition and
generation sub-systems use these signals to manage and synchronize acquisitions and
generations. These signals can come from the following sources:
• C Series modules programmed in Real-Time (NI-DAQmx) mode
• User input through the PFI terminals using parallel digital C Series modules or the
cRIO-905x PFI 0 terminal
• FPGA or DAQ ASIC using the cRIO trigger bus to share hardware triggers and signals
between the LabVIEW FPGA and DAQmx applications
Clock Routing
The following figure shows the clock routing circuitry of the cRIO-905x.
Figure 6. Clock Routing Circuitry of the cRIO-905x
Onboard
100 MHz
Oscillator
Clock
Generator
DAQ ASIC
RIO FPGA
cRIO Trigger Bus
80 MHz Timebase
20 MHz Timebase
100 kHz Timebase
13.1072 MHz Timebase
12.8 MHz Timebase
10 MHz Timebase
40 MHz Onboard Clock
÷200
13.1072 MHz Carrier Clock
12.8 MHz Carrier Clock
10 MHz Carrier Clock
÷2
÷4
Note When switching between programming modes, you may notice the terms
timebase and clock used interchangeably. This is due to the DAQ ASIC and the RIO
FPGA using different terminology for timing and clock mechanisms. The
documentation will use the term based on the programming mode discussed.
80 MHz Timebase
When programming C Series modules in Real-Time (NI-DAQmx) mode, the 80 MHz
timebase can function as the source input to the 32-bit general-purpose counter/timers. The
80 MHz timebase is generated from the onboard oscillator.
NI cRIO-905x User Manual | © National Instruments | 15

20 MHz and 100 kHz Timebases
When programming C Series modules in Real-Time (NI-DAQmx) mode, the 20 MHz and
100 kHz timebases can be used to generate many of the analog input and analog output timing
signals. These timebases can also function as the source input to the 32-bit general-purpose
counter/timers. The 20 MHz and 100 kHz timebases are generated by dividing down the
80 MHz timebase, as shown in the previous figure.
40 MHz Onboard Clock
When programming C Series modules in FPGA mode, the 40 MHz onboard clock is used as
the top-level clock for your LabVIEW FPGA application and C Series module IO nodes. The
40 MHz onboard clock can be used to clock single-cycle timed loops. Derived clocks of
varying frequency can be generated from the 40 MHz onboard clock. The 40 MHz onboard
clock is phase aligned with the incoming 80 MHz clock.
13.1072 MHz, 12.8 MHz, and 10 MHz Timebases and Carrier
Clocks
When programming C Series modules in Real-Time (NI-DAQmx) mode, the 13.1072 MHz,
12.8 MHz, and 10 MHz timebases can be used to generate many of the analog input and
analog output timing signals. These timebases can also function as the source input to the 32-
bit general-purpose counter/timers. The 13.1072 MHz, 12.8 MHz, and 10 MHz timebases are
generated directly from the onboard clock generator.
When programming C Series modules in FPGA mode, the 13.1072 MHz, 12.8 MHz, and
10 MHz carrier clocks can be used as the master clock for C Series analog input and analog
output modules. The 13.1072 MHz, 12.8 MHz, and 10 MHz carrier clocks are available as IO
Nodes in LabVIEW FPGA applications and can be used to correlate the onboard clocks with
self-timed C Series modules containing free-running clocks.
Synchronization Across a Network
Internal Timebase
The onboard 100 MHz oscillator automatically synchronizes to other network-synchronized
devices that are part of the local IEEE 802.1AS or IEEE 1588-2008 subnet, depending on the
active time reference that is being used on the controller.
The 80 MHz, 40 MHz, 20 MHz, 100 kHz, 13.1072 MHz, 12.8 MHz, and 10 MHz timebases
are derived from the onboard oscillator and are synchronized to it. Therefore, the timebases are
also synchronized to other network-synchronized timebases on the IEEE 802.1AS or
IEEE 1588-2008 subnet. This enables analog input, analog output, digital I/O, and counter/
timers to be synchronized to other chassis across a distributed network.
When programming C Series modules in FPGA mode, the Time Synchronization IO Nodes
can be used to synchronize the LabVIEW FPGA application to other network-synchronized
devices.
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Network-based Synchronization
IEEE 1588, also known as the precision time protocol (PTP), is an Ethernet-based
synchronization method designed for cabled, local networks. The PTP protocol provides a
fault tolerant method of synchronizing all participating clocks to the highest quality clock in
the network. This method of synchronization between networked devices uses packet-based
communication and is possible over the long distances allowed for each Ethernet link, without
signal propagation impact. IEEE 1588 has many different profiles, such as
IEEE 802.1AS-2011, each of which use different features. Because the profiles are not
interoperable with each other, make sure it is known which profile is implemented on the
device. For devices on the network to synchronize with each other using IEEE 1588, all
devices must be compatible with the desired IEEE 1588 profile and must all be connected
within the selected IEEE 1588 profile-compliant network infrastructure.
The cRIO-905x controllers are compatible with both the IEEE 802.1AS-2011 profile and the
IEEE 1588-2008 (1588v2) Delay Request-Response profile. However, each network port must
be configured individually to the specific profile required for the network.
Differences Between IEEE 802.1AS-2011 and IEEE 1588-2008
IEEE 802.1AS-2011, also known as the generalized precision time protocol (gPTP), is a
profile of IEEE 1588. A cRIO-905x controller can be configured to use either the
IEEE 802.1AS-2011 profile or the IEEE 1588-2008 profile by configuring the port’s time
reference. If a user does not explicitly specify which time reference to use a cRIO-905x
controller will default to use the IEEE 802.1AS-2011 profile. There are some differences
between the IEEE 802.1AS-2011 profile and the IEEE 1588-2008 profile which are called out
below:
• IEEE 802.1AS-2011 assumes all communication between devices is done on the OSI
layer 2, while IEEE 1588-2008 can support various layer 2 and layer 3-4 communication
methods. The IEEE 1588-2008 profile National Instruments implements on the
cRIO-905x only supports layer 3-4 communication methods. Operating on the layer 2
yields better performance for the IEEE 802.1AS-2011.
• IEEE 802.1AS-2011 only communicates gPTP information directly with other
IEEE 802.1AS devices within a system. Therefore, there must be IEEE 802.1AS-2011
support along the entire path from one IEEE 802.1AS-2011 device to another. With
IEEE 1588-2008, it is possible to use non-IEEE 1588-2008 switches between two
IEEE 1588-2008 devices. The benefit of having IEEE 802.1AS-2011 support along the
entire path is a faster performance and lower jitter compared to IEEE 1588-2008.
• With IEEE 802.1AS-2011 there are only two types of time-aware systems: time-aware
end stations and time-aware bridges. Whereas with IEEE 1588-2008, there are the
following: ordinary clock, boundary clock, end-to-end transparent clock and a time-aware
bridges. Based on these factors, IEEE 802.1AS-2011 can reduce complexity and
configuration challenges compared to IEEE 1588-2008. A cRIO-905x controller acts as a
time-aware end station for both protocols.
NI cRIO-905x User Manual | © National Instruments | 17

IEEE 1588 External Switch Requirements
To take advantage of the network synchronization features of the cRIO-905x controllers,
ensure that your network infrastructure meets certain requirements depending on which
IEEE 1588 profile is implemented for your application:
• IEEE 802.1AS-2011 support—Automatically enables timebase synchronization and
enables the use of time-based triggers and timestamping between devices across the
network. Synchronization performance will meet NI product specifications.
• IEEE 1588-2008 support—Enables timebase synchronization and enables the use of time-
based triggers and timestamping between devices across the network. Synchronization
performance will vary and may not meet NI product specifications. As a default
configuration for IEEE 1588-2008, NI supports the IEEE 1588 Delay Request-Response
profile, using the UDP over IP transport (layer 3-4).
Battery
The cRIO-905x contains a lithium cell battery that stores the system clock information when
the cRIO-905x is powered off. There is only a slight drain on the battery when power is
applied to the cRIO-905x power connector. The rate at which the battery drains when power is
disconnected depends on the ambient storage temperature. For longer battery life, store the
cRIO-905x at a cooler temperature and apply power to the power connector. Refer to the
specifications on ni.com/manuals for the expected battery lifetime.
The battery is not user-replaceable. If you need to replace the battery, contact NI. Refer to the
controller specifications on ni.com/manuals for information about battery disposal.
File System
LabVIEW mounts USB devices and microSD cards to the media/sdx1 directory and creates
symbolic links /u, /v, /w, or /x to the media mount point, starting with /u if it is available.
To prevent any file corruption to external storage devices, verify that any file IO operations
with the specific drive finish before removing the device. Refer to the LabVIEW Help for more
information.
The file system of the cRIO-905x follows conventions established for UNIX-style operating
systems. Other LabVIEW Real-Time targets follow Microsoft Windows-style conventions. In
order to facilitate the porting of applications from those targets, this target supports the
Windows-style /C home directory. This path is bound to the UNIX-style directory /home/
lvuser.
Various LabVIEW Real-Time system files which would be accessible from C: (or /C) on
other LabVIEW Real-Time targets are found in different locations on this target.
UNIX-style file systems support the concept of a symbolic link, which allows access to a file
using an alternative file path. For example, it is possible to link /C/ni-rt/system, where
dynamic libraries are deployed on other LabVIEW Real-Time targets, to /usr/local/lib,
where they are stored on the cRIO-905x, if the application requires this.
For more information, visit ni.com/info and enter the Info Code RT_Paths.
18 | ni.com | NI cRIO-905x User Manual

Mounting the Controller
To obtain the maximum ambient temperature, you must mount the cRIO-905x in the reference
mounting configuration shown in the following image. Mounting the cRIO-905x in the
reference mounting configuration ensures that your system will operate correctly across the
full operating temperature range and provide optimal C Series module accuracy. Observe the
following guidelines to mount the cRIO-905x in the reference mounting configuration.
Figure 7. System Mounting Configuration
3
4
1
2
NI cRIO-905x User Manual | © National Instruments | 19

1
Vertical mounting orientation.
2
Mounting substrate options:
• Mount the cRIO-905x directly to a metallic surface that is at least 1.6 mm
(0.062 in.) thick and extends a minimum of 101.6 mm (4 in.) beyond all edges of
the device.
• Use the NI Panel Mounting Kit to mount the cRIO-905x to a metallic surface that is
at least 1.6 mm (0.062 in.) thick and extends a minimum of 101.6 mm (4 in.)
beyond all edges of the device.
3
Observe the minimum spacing dimensions in the Mounting Requirements section.
4
Allow space for cabling clearance according to the Mounting Requirements section.
Tip Before mounting the controller, record the serial number from the side of the
cRIO-905x so that you can identify the cRIO-905x in MAX. You will be unable to
read the serial number after you mount the controller.
Alternative Mounting Configurations
The maximum operating temperature may be reduced for any mounting configuration other
than the reference mounting configuration. A 10 °C (18 °F) reduction in maximum operating
temperature is sufficient for most alternate mounting configurations. Follow the guidelines
above for all mounting configurations. The published accuracy specifications, although not
guaranteed for alternate mounting configurations, may be met depending on the system power
and the thermal performance of the alternate mounting configuration. Contact NI for further
details regarding the impact of common alternate mounting configurations on maximum
operating temperature and module accuracy.
Contact NI for further details regarding the system impact of common alternative mounting
configurations.
Mounting Requirements
Figure 8. Minimum Spacing Dimensions
1 2 3 4 5 6 7 8
25.4 mm
(1.00 in.)
20 | ni.com | NI cRIO-905x User Manual