LabVIEW Real-Time (RT) SupportFrequently Asked Questions
Overview
Software What are the programming differences between LabVIEW and LabVIEW Real-Time? LabVIEW Real-Time is a superset of LabVIEW programming. Data acquisition, analysis, data transfer, and other VI's work in the Real-Time environment exactly as they do in a Windows system. However, when programming a deterministic application you will have special considerations, such as paying attention to threads and priorities. Certain VI's will compile in the Real-Time system but may harm determinism. There are also hardware specific considerations. For example, a small number of LabVIEW functions will not run on the RT Series board because the boards do not have certain hardware features. For example, there is no hard drive, so you cannot do file I/O; and with no GPIB or IEEE-488 port, those calls will not work; etc. Attempting to use these unsupported functions in an embedded LabVIEW Real-Time application will result in standard LabVIEW error codes. The PXI controller supports additional functionality such as file I/O, onboard GPIB commands, serial functions, and so on. Windows-specific functionality, such as ActiveX, are not supported. click here to view a presentation on LabVIEW Real-Time programming. What happens if Windows or the host PC crashes? An embedded LabVIEW Real-Time application running on the independent processor of the RT Series board or the PXI controller will continue to run even if the host PC and Windows crashes. As long as power is supplied, a LabVIEW Real-Time application will continue to run. The board power supply depends on the host machine, but the PXI controller power supply is independent of the host machine. You can then do a soft reboot on the host PC to re-establish a connection to the embedded LabVIEW Real-Time application. How do I communicate to the embedded LabVIEW Real-Time code running on the RT Series board? You can access an embedded LabVIEW Real-Time application and show the front panel and block diagrams with the RT Development System running on the host PC. Or, you can write another host LabVIEW application to talk to the embedded LabVIEW Real-Time application. Specifically, you can use one of the following protocols for communicating with your target processor:
Can LabVIEW users upgrade to LabVIEW Real-Time? Yes, please use Upgrade Advisor to configure your upgrade. Can I use LabWindows/CVI or any other external compiler to program the RT Series hardware? Not at this time. However, as of LabWindows/CVI 6.0, you can communicate with your 7030/60XX RT hardware using shared memory. To do this, use the LabVIEW RT communications functions under toolslib\cvirtsup. You can also build dll's in LabWindows/CVI that can be called by LabVIEW RT. To do this, set your dll target settings to build a dll for LabVIEW Real-Time only. RT Series PXI Controller What is a RT Series PXI controller? The RT Series PXI controller is any National Instruments PXI controller with a preinstalled hard drive containing the RT engine software running in a real-time operating system, rather than the Windows OS. This controller can control an entire chassis of data acquisition boards in real-time. It is a headless, embedded real-time system, that can communicate to Windows host applications, or run completely standalone. This PXI/CompactPCI form factor and scalable I/O counts can be ideal for machine monitoring and control, real-time test, and so on. The RT Series PXI controllers are identical in hardware to standard PXI controllers; the difference lies in the installed software. In fact, a standard PXI controller with Windows installed can be used in Real Time Applications - you will simply boot into the Real Time Operating System using a floppy. Click here for more information about the RT PXI controllers. What chassis can I use with the controller? You can use any of the National Instruments PXI chassis except the PXI-1020 and the PXI-1025 (with built-in display screens). What modules are supported with the controller? All PXI data acquisition modules can be used with the RT controller. As of LabVIEW Real-Time 6i, NI-FlexMotion, NI-CAN and NI-serial boards are also supported. Also, you can now use NI-VISA to communicate with any third party hardware that supports the VISA communication standard. No image acquisition, instruments, or other plug-in modules are supported at this time. However, as PXI is a standard industrial platform, we plan to support machine vision, and other modules to build a complete real-time system for applications such as machine monitoring and control, real-time test, and more. Please use PXI Configurator to configure your RT system. What onboard ports are supported on the RT controller? On the 8156B controller, the ethernet, GPIB, hardware watchdog, and two onboard serial ports are supported. On the 8170, the onboard serial ports and hardware watchdog are supported. On both controllers, The video, mouse, keyboard, USB, and other connectors onboard the controller are not supported at this time. If you need to send status messages to a terminal, use the serial port. Can I do file I/O or datalogging on the RT controller hard drive? Yes, file I/O is supported on the RT controller. Can I use more than one controller on a network? Yes, multiple RT controllers can run on a single network. Can I build applications that reside on the controller? Yes, because there is permanent storage on the controller, you can distribute applications saved on the controller. Can I build applications that run at bootup of the controller? Yes, you can build a standalone executable such that it runs as soon as the controller boots up. Or you can build an executable that starts running from a remote command by a host Windows PC. RT Series Data Acquisition What is a RT Series intelligent DAQ board? An intelligent RT Series DAQ board is composed of a processor "mother board" with an attached DAQ daughter board. The independent processor ensures reliable and real-time operation from the host PC and Windows. The DAQ daughter board is created from our existing PXI DAQ board technologies. The first three RT Series DAQ boards have the same functionality as a PXI-6040E, PXI-6030E, and PXI-6533. The boards are single-slot PCI and double-slot PXI. Click here for more information about the RT series DAQ boards. What is the processor and memory on the intelligent RT Series boards? We use an AMD 486DX5 (also called the 5x86) processor that runs at 133 MHz. We have 8 MB available for user-definable programs. The user will also have access to 1 KB of shared memory. Must you purchase a separate processor board and a separate DAQ daughter board? No, the RT Series boards are complete solutions. You only order a single intelligent RT Series board with specific DAQ functionality. What DAQ accessories work with RT Series boards? All NI-DAQ accessories, such as SCXI and the AMUX-64, work with RT Series boards. Can I have more than one RT Series board in a system? Yes, the boards can be synchronized with RTSI. How many LabVIEW Real-Time applications can run at once on a RT Series board? Numerous embedded LabVIEW Real-Time applications can run at once on a RT Series board provided you have enough memory. More LabVIEW Real-Time applications mean that the over-all system speed will decrease, but you will not compromise real-time performance. Can an intelligent RT Series DAQ board control other DAQ boards in the host PC bus or PXI system? No. The National Instruments RT Series DAQ boards handles RTSI, but RTSI is for timing, triggering, and synchronization only. How do the intelligent RT Series DAQ boards compare with the 45XX dynamic signal analyzer (DSA) that National Instruments also sells? The DSA boards are high-performance instrument cards designed specifically for making sound and vibration measurements. As a result, the DSA is programmed with instrument-like commands and has hardware that is tuned for those measurements. The DSA has hardware features like simultaneous sampling, anti-aliasing filters, and overrange detection, while the intelligent RT Series DAQ hardware remains general purpose. The RT Series is designed for real-time control and complete programmability with LabVIEW. Can I download LabVIEW Real-Time code to the RT Series board and move the board to another PCI computer to execute the embedded code? No, not at this time. How does the board naming work? or What is a 7030/6XXX? Because the board has two sections, there are two device numbers that are assigned in NI-DAQ. There is the processor board (7030) where the LabVIEW Real-Time code runs and the attached DAQ daughter board (6040E, 6030E, or 6533). When you purchase a board you purchase a PXI or PCI 7030 with specific DAQ board functionality. For example, the 12-bit RT Series board is a 7030 with 6040E, or just 7030/6040E.
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