The controllers can operate as stand-alone devices to expand the capabilities of the platform while taking advantage of the modularity and flexibility of the C Series platform and LabVIEW system design software. A controller system is composed of an embedded controller, up to eight I/O module slots, C Series I/O modules, an OS, and software. The controller includes a powerful Intel multicore processor to run an embedded OS and a hard disk drive with up to 32 GB of nonvolatile storage for data logging. In addition to the onboard storage, the controllers also offer removable SD storage to easily save and access your data. The controllers offer module options with integrated signal conditioning for almost any sensor type as well as standard connectivity such as USB, Ethernet, CAN/LIN, and RS232 serial for expansion I/O and other third-party peripheral devices.
Figure 1. CompactDAQ controllers are composed of I/O module slots, an embedded processor, C Series I/O modules, software, and optional peripherals.
2. High-Performance Multicore Processing
CompactDAQ controllers feature a dual-core Intel processor for intense processing tasks. With multicore processors, you can execute independent tasks, or threads, simultaneously to drastically reduce the time required to perform operations. LabVIEW makes it easy to develop an application that takes advantage of this multicore technology by automatically dividing each operation into multiple threads. The complex task of thread management within the processor is transparently built into graphical programming.
|Clock Frequency||1.33 GHz||1.33 GHz||1.91 GHz||1.06 GHz||1.33 GHz/2.4 GHz (Turbo)|
|Active Management Technology (AMT)||No||No||No||No||Yes|
Table 1. CompactDAQ controllers use advanced multicore Intel processors.
To enhance the performance and functionality of your CompactDAQ application, Intel processors offer several technologies:
- Intel Hyper-Threading improves multicore performance by giving each processor core the ability to execute two threads in parallel, doubling the number of apparent processor cores available to software. This allows applications running on the cDAQ-9139 to execute four threads in parallel, further increasing performance.
- Intel Turbo Boost provides increased processor clock frequency during times of high workload. When your application calls for faster clock frequencies during intense calculations, the processor’s clock frequency automatically increases at regular increments until demand is met, or until factors such as temperature and load on other processor cores cause the clock speed to reduce back to its base operating frequency. This ensures that you always get the maximum performance while keeping the processor within its designed safety limits.
- Intel Active Management Technology (AMT) gives advanced users the ability to remotely manage their CompactDAQ systems. This low-level hardware access is performed via the primary Ethernet interface and allows the remote user to power up or down their CompactDAQ system, check the current system status, redirect the console output to the remote user, and many other management tasks without any interaction with the CompactDAQ software.
3. Embedded OSs
The controllers feature a CompactDAQ chassis with an integrated processor to run embedded OSs. You can use Windows Embedded Standard 7 (WES7) for an extensive ecosystem of software and a familiar user experience or choose LabVIEW Real-Time for headless operation and increased reliability.
Reliability is critical to guarantee that an application runs correctly for an extended time, which is needed for many embedded applications. Both WES7 and LabVIEW Real-Time have features and properties that make them a good choice for tasks requiring extended operation. WES7 also gives you the ability to use the extensive Windows software ecosystem and the LabVIEW for Windows platform. Using WES7, you can take advantage of functions found in .NET assemblies, ActiveX controls, and DLLs; or directly connect to a remote database for logging with ease. Additionally, you can use the built-in VGA or miniDisplay port outputs to implement your user interface, which reduces system costs and maintenance requirements by eliminating the need for a dedicated user interface computer.
LabVIEW Real-Time OS components have been reduced to the minimum required, decreasing the probability of system failure due to crashes and other unforeseen problems. General-purpose OSs must attempt to provide resources and execution time to many different applications. Each additional application increases the opportunity and frequency of system failure. LabVIEW Real-Time also has features, such as the Reliance file system and watchdog timers, that further ensure application reliability over an extended time. The Reliance file system by Datalight is designed for embedded systems that require high reliability. It provides immunity to file corruption that results from system events such as unexpected power loss. Watchdog timers ensure that, in the event of an application failure, a system can be brought back to an operating state quickly and automatically.
With the new NI Linux Real-Time OS found on the cDAQ-9132/9133/9134/9135 controllers, real-time operations can also now take advantage of live display. By using the built-in miniDisplay port on the controllers, you can connect directly to a screen or human machine interface (HMI), which eliminates the need for a dedicated user interface computer.
4. Measurements Timing and Synchronization
Because CompactDAQ is a modular system, you can add more measurement types and channels to the system by simply plugging in additional modules. All modules are hot-swappable and are automatically detected when you insert them into a CompactDAQ system. Modules are automatically synchronized, and a single CompactDAQ system can simultaneously stream high-speed analog input, analog output, digital input, and digital output.
The analog-to-digital converter (ADC) is a vital piece of any measurement system. ADCs need clock signals to designate when samples are to be acquired. Many systems have multiple ADCs that share the same clock to synchronize all of the channels’ measurements. CompactDAQ systems have the advantage of flexibility when it comes to timing engines and go beyond this standard synchronization.
Multiple Timing Engines for Multiple Rates
CompactDAQ systems have three analog input timing engines. You can divide all your analog inputs in up to three different groups known as tasks. Each task can run at a separate rate, as seen in Figure 2. This is ideal when combining temperature measurements, which are often slow, with higher speed measurements such as sound and vibration. The three tasks operate independently but can be started simultaneously. All channels within a single task are automatically synchronized and returned at the requested rate. All modules can be combined in a single task to easily synchronize all channels to the same clock.
Figure 2. Different analog input tasks can run at different rates in the same chassis.
Designated Timing Engines for Analog and Digital Output
CompactDAQ can perform up to seven tasks simultaneously. You can choose from several task options:
- Analog input with up to three timing engines
- Analog output with designated timing engine
- Digital input with designated timing engine
- Digital output with designated timing engine
- Counter/timer tasks for quadrature, PWM, event, period, or frequency measurement
By having a designated resource, digital and analog output tasks can run independently without having to share a clock signal from another task. This makes the programming easier and more intuitive. The multiple timing engines and ability to route and share resources provide a level of flexibility to CompactDAQ unequaled by most off-the-shelf DAQ systems.
5. C Series I/O Channel Expansion
CompactDAQ controllers can provide up to eight slots of integrated C Series I/O capacity that you can increase with various C Series I/O expansion options. These expansion options are USB, Ethernet, and wireless CompactDAQ chassis that can stream directly to CompactDAQ controllers. (Note: Windows-based CompactDAQ controllers support all CompactDAQ expansion options; however, RTOS-based CompactDAQ controllers running LabVIEW Real-Time support only USB CompactDAQ chassis for expansion I/O.)
With these expansion methods, you can incorporate any combination of over 60 measurement-specific C Series I/O modules. With this wide selection of measurement modules, you can tailor your system to your exact I/O requirements.
Figure 3. The CompactDAQ platform includes 1-, 4-, 8-, and 14-slot chassis options for expansion.
6. Integrating Displays and External Devices
Creating an HMI is an important step when developing any embedded or industrial system. CompactDAQ controllers include integrated VGA graphics or miniDisplayPort, which greatly simplify HMI development. Using WES7 or NI Linux Real-Time and a monitor or flat panel touch screen, you can develop your LabVIEW application and use its front panel as your user interface. This not only reduces development time by eliminating the development of a separate HMI application, but also reduces cost by replacing the additional PC or touch panel computer with a low-cost monitor. Alternatively, you can use the LabVIEW Data Dashboard for iOS and Android mobile devices to control and monitor your system from your smartphone or tablet on the go.
Figure 4. Directly connect an HMI or configure a mobile device to monitor and interact with stand-alone CompactDAQ.
CompactDAQ controllers are ideal for applications that involve synchronized video and measurements. Use the dual Gigabit Ethernet ports to connect to a range of GigE Vision cameras and perform fast, high-resolution image acquisition and processing tasks with both LabVIEW Real-Time and WES7. Take advantage of the high-performance NI-IMAQdx driver and hundreds of algorithms in the Vision Development Module imaging library to develop vision applications that involve tasks such as image enhancement, pattern matching, and object measurement.
Figure 5. Use the dual Gigabit Ethernet ports to connect to a range of GigE Vision cameras.
Connect to a wide array of additional hardware through the large selection of connectivity options on CompactDAQ controllers. You can use the Hi-Speed USB ports to connect to peripherals such as a keyboard or mouse, or use them to log data to an external storage medium. Choose either the RS232 or RS485/422 serial port to connect to a multitude of devices such as a GPS. Use the integrated CAN/LIN port to communicate over the protocol to a wide variety of devices.
No measurement system is complete without software. You can use LabVIEW system design software to completely customize your stand-alone measurement system. LabVIEW provides a single environment in which you can acquire, analyze, and present data and it abstracts low-level programming calls. This abstraction means LabVIEW, in combination with the NI-DAQmx driver, can adapt to changing requirements and technologies over time to help you keep your application on pace with the rest of the industry.
In LabVIEW, NI offers data-logging examples, templates, and sample projects for CompactDAQ controllers to complement the hundreds of NI-DAQmx examples already available. These options provide different starting points for novice programmers interested in seeing measurements fast, and experienced programmers seeking scalable software architectures designed and recommended by LabVIEW developers. With tools and features focused on user proficiency, LabVIEW helps engineers and scientist of all levels to innovate faster.
Users who want a turnkey solution can choose configuration-based software from the LabVIEW Tools Network or take advantage of over 600 companies in the NI Alliance Partner Network for a custom solution. These partners specialize in integration and customization services with LabVIEW and NI DAQ products. No matter the application size, complexity, or need for customization, there is a software solution to meet the needs of programmers and nonprogrammers.
8. Additional Resources
- Learn About the Advantages of CompactDAQ Controllers
- Download Technical Resources for CompactDAQ Controllers
- Compare CompactDAQ and CompactRIO
- Specifications Explained: cDAQ and cRIO Chassis and Controllers
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