PXI and PXIe for Real-Time Applications Murali Ravindran PXI Product Manager National Instruments

This picture shows Boeing’s phased array of 448 microphones and the eight PXI chassis that were distributed in a 250 ft. wide by 300 ft. long area and synchronized to within one degree at 93 kHz.

What is PXI? PXI = PCI eXtensions for Instrumentation Open specification governed by the PXI Systems Alliance (PXISA) and introduced in 1997 PC-based platform optimized for test, measurement, and control PCI electrical-bus with the rugged, modular, Eurocard mechanical packaging of CompactPCI Advanced timing and synchronization features PXI (PCI eXtensions for Instrumentation) is an open specification governed by the PXI Systems Alliance (PXISA) that defines a rugged, CompactPCI-based platform optimized for test, measurement, and control. PXI combines PCI electrical-bus features with the rugged, modular, Eurocard packaging of CompactPCI and adds specialized synchronization buses. This makes it both a high-performance and low-cost deployment platform for measurement and automation systems. These systems serve applications such as manufacturing test, military and aerospace, machine monitoring, automotive, and industrial test.

PXI Combines Standard Technologies PXI Backplane PCI bus Timing and Synchronization Controller Embedded PC or remote PC / laptop interface Runs all standard software Chassis PXI systems are comprised of three basic components – chassis (which includes the PXI backplane), controller, and peripheral modules. The chassis provides the rugged and modular packaging for the system. Chassis range in size from 4 to 26 slots. The chassis contains the high-performance PXI backplane, which includes the PCI bus and timing and synchronization buses. All PXI systems include a controller. Controller options include remote control from standard desktop and laptop PCs, 1U rackmount controllers, and high-performance embedded controllers. Because PXI embedded controllers are built using standard PC components, they run standard operating systems, such as Windows XP, and applications, such as Microsoft Excel. Over 1,000 different peripheral modules are available from the 70+ members of the PXISA. Modules are available for instrumentation, data acquisition, control, interfacing to buses, etc. Peripheral Modules

Industry Bus Performance 10000 1000 100 10 1 0.1 Good Better Best PCI/PXI (32/33) Max Bandwidth (MB/s) Gigabit Ethernet USB 2.0 IEEE 1394a VME/VXI Fast Ethernet GPIB (HS 488) This graph shows various busses and their associated bandwidth and latency. Latency or the minimum time to do a single transaction is decreasing along the x axis and bandwidth is increasing along the y axis. To highlight popular industry busses, you can see where GPIB, USB 2.0 and the Ethernet families sit relative to each other. PXI uses PCI communication which is the highest-bandwidth and lowest-latency bus on this chart, providing up to 132 MB/s. In addition to bus throughput performance, PXI has timing and triggering lines for module synchronization… USB 1.1 GPIB (488.1) Approximate Latency (μs)

Leveraging PCI Express Data bus for PXI Data bus for PXI Express PCI 132 MB/s Shared Parallel Bus PCI Express 250 MB/s to 4 GB/s Independent Serial Bus Modules up to 1 GB/s Host up to 6 GB/s (2-link) 4 GB/s (4-link) The PXI Express spec allows for a maximum of 4 (max link width x4) links for a total of x16 to the host OR 2 (max link width of one x16 and one x8) for a total of x24 to the host.

Industry Bus Performance 10000 1000 100 10 1 0.1 PCI / PXI Express (x4) Good Better Best PCI/PXI (32/33) Max Bandwidth (MB/s) Gigabit Ethernet USB 2.0 IEEE 1394a VME/VXI Fast Ethernet GPIB (HS 488) This is the same graph from the “What is PXI” section that shows various busses and their associated bandwidth and latency. Latency or the minimum time to do a single transaction is decreasing along the x axis and bandwidth is increasing along the y axis. A “by four” PCI express link has the lowest latency and furthers the bandwidth lead over other busses. A x4 link can provide up to 1 GB of data in each direction USB 1.1 GPIB (488.1) Approximate Latency (μs)

PXI Timing and Triggering Star Trigger Bus 10 MHz CLK Controller System Local Bus Peripheral Peripheral Peripheral Peripheral Timing Slot System PXI Trigger Bus 0..7 The additional Timing and triggering features of PXI allow modules to synchronize themselves in a variety of ways. The first feature is a 10 MHz system clock that is provided to each peripheral module. Modules can synchronize to this clock to achieve synchronization. The second feature is the PXI Trigger bus. This parallel bus provides 8 trigger lines that can be used to send triggers or signals between devices. Because the bus is a parallel bus, skew can be introduced by bus load and trace-length mismatch. To provide a method for limited-skew synchronization, PXI also incorporates.. A Star Trigger bus. This single-source, single destination bus can be sourced from the system timing slot and each trace is matched length to ensure minimal skew between devices. The last synchronization bus is the Local Bus. This bus provides 13 to the left and 13 lines to the right peripheral module. PXI_CLK10 10MHz point to point <1ns skew PXI_STAR Point to point <1ns skew PXI_TRIG 8-line parallel trigger lines

Additional Features in PXIe Supplied Power and Cooling Increase Geographical Addressing Timing and Synchronization 100 MHz differential clock Differential Star Triggers Available power to modules has increased to 140 W for the system controller and 30 W for a peripheral module to enable higher-performance products. Geographical addressing allows for software to read the slot position of a PXI Express module independent of the driver being used for the device. Additional timing and triggering signals improve upon the first revision of PXI (PXI-1). To look at these timing and triggering signals in greater detail…

PXI Trigger Bus (8 TTL Triggers) 100 MHz Differential CLK PXI Express Star Trigger 10 MHz CLK PXI Express Controller System PXI Express Peripheral Hybrid PXI Express Peripheral Hybrid PXI Express Peripheral Hybrid PXI Express Timing Slot System Peripheral PXI PXI Express adds additional signals to the PXI-1 specification discussed in the first section. The diagram above is a PXI Express extension of the PXI diagram used in the first section. Note that all slots are PXI Express capable but the rightmost slot. All PXI-1 timing and triggering features but local bus are still distributed to every peripheral slot. In this diagram, PXI Express additions to PXI-1 timing and triggering features are illustrated in orange. The first addition is a 100MHz differential clock. As with other PXI Express timing and triggering features, the clock is only routed to PXI Express slots. PXI Trigger Bus (8 TTL Triggers)

Comparing PXIe_CLK100 and PXI_CLK10 PXI_CLK10 preserves compatibility with PXI modules PXI_CLK10 is synchronous to PXIe_CLK100 Specifications comparison PXIe_CLK100 PXI_CLK10 Frequency 100 MHz 10 MHz Logic Family LVPECL, Diff TTL, SE Freq. Accuracy ±100 ppm or better Skew ≤ 200 ps ≤ 1 ns Two important details to note are that PXI_Clk10 is synchronous to PXIe_CLK100 so devices that use either PXI_CLK10 or PXIe_CLK100 as a reference clock are synchronized Additionally, the skew of the new clock has been improved from a module-to-module skew of <= 1ns to < or = 200ps to minimize skew between peripheral devices.

PXI Trigger Bus (8 TTL Triggers) 100 MHz Differential CLK PXI Express Star Trigger SYNC Control SYNC100 10 MHz CLK PXI Express Controller System PXI Express Peripheral Hybrid PXI Express Peripheral Hybrid PXI Express Peripheral Hybrid PXI Express Timing Slot System Peripheral PXI-1 Another addition in PXIe is the Sync100 signal. This signal can be controlled by the system timing module… PXI Trigger Bus (8 TTL Triggers)

PXIe_SYNC100 Delivered to each PXIe peripheral slot Differential LVPECL signal 10ns pulse coordinated to PXI_CLK10 The Sync100 signal is a differential signal delivered to each PXIe peripheral slot. Sync100 provides a 10ns pulse that is coordinated with the rising edge of PXI_CLK10. As you can see from the timing diagram, a 10ns pulse on Sync100 immediately precedes a rising edge of PXI_CLK10.

PXI Trigger Bus (8 TTL Triggers) 100 MHz Differential CLK PXI Express Star Trigger SYNC Control SYNC100 10 MHz CLK PXI Express Controller System PXI Express Peripheral Hybrid PXI Express Peripheral Hybrid PXI Express Peripheral Hybrid PXI Express Timing Slot System Peripheral PXI-1 Differential Star Triggers To minimize skew between peripheral device, the PXI-1 specification provides a point-to-point Star trigger for matched trace-length signaling from the system timing slot. PXI Express adds three Differential Star triggers to the specification to allow for higher frequency signaling with less jitter. PXI Trigger Bus (8 TTL Triggers)

Differential Star Triggers PXIe_DSTARA, PXIe_DSTARB, PXIe_DSTARC Differential, point-to-point connections Matched length to within 150ps PXIe Peripheral Slots and the System Timing Slot Allows for increased clock frequency distribution The three PXI Express star triggers are named DSTAR a, b and c. These are matched-length differential point-to-point connections between the system timing module and PXI Express peripheral modules

Integrating PCI Express into the PXI Backplane Up to 2 GB/s dedicated bandwidth per slot Enhanced synchronization capabilities 100 MHz differential clock, differential triggering Backwards compatibility Complete software compatibility Hybrid slot definition - install modules with either PCI or PCI Express signaling in a single slot Differential triggering gives a cleaner signal so better accuracy The next step is to integrate the PCI Express bus into the PXI backplane. The PXI Express backplane integrates PCI Express while still preserving compatibility with current PXI modules, users benefit from increasing bandwidth while maintaining backward compatibility with existing systems. PXI Express specifies hybrid slots to deliver signals for both PCI and PCI Express. With PCI Express electrical lines connecting the system slot controller to the hybrid slots of the backplane, PXI Express provides a high bandwidth path from the controller to backplane slots. Using an inexpensive PCI Express-to-PCI bridge, PXI Express provides PCI signaling to all PXI and PXI Express slots to ensure compatibility with PXI modules on the backplane. With the ability to support up to a x16 PCI Express link in addition to a x8 link, the system controller slot provides a total of 6 GB/s bandwidth to the PXI Express backplane, representing more than a 45X improvement in PXI backplane throughput.

Real Time Architectures on PXI Non-Deterministic Deterministic

HW-Timed I/O Non-Deterministic Deterministic Controller I/O Element Non-RT OS Windows, Linux, etc. FIFO Data Bus Clock Software Task 1 DAC

Clocked I/O Non-Deterministic Deterministic PXI System Controller PXI Timing Backplane I/O Element Non-RT OS Windows, Linux, etc. Software Task 1 DAC DAC ADC

RTOS Non-Deterministic Deterministic PXI System Controller PXI Timing Backplane I/O Element RTOS LVRT, RT Linux DAC Software Task 1 DAC ADC

On-Board Processing Non-Deterministic Deterministic PXI System Controller PXI Timing Backplane I/O Element Non-RT OS Windows, Linux, etc. Smart I/O Element “RIO” FPGA Task2 Software Task 1 DAC ADC ADC

This picture shows Boeing’s phased array of 448 microphones and the eight PXI chassis that were distributed in a 250 ft. wide by 300 ft. long area and synchronized to within one degree at 93 kHz. PXI Chassis

Partial PXISA Member List Here is a partial list of the PXISA membership. A complete list is available at www.pxisa.org. Complete list at pxisa.org

PXI – The Fastest Growing Standard in Test Actual Forecast 23% CAGR forecast for 2006 – 2012 Source: World VXI & PXI Test Equipment Markets, Frost & Sullivan, September 2006 Number of Systems Per Year More than 1,500 PXI Products Available!

Future PXI Growth Vs. Other Areas of T&M Growth Through 2011 Oscilloscopes 2.9% Multimeters 2.4% Overall T&M 5.0% PXI 25.1% Electronic Design 2006 Technology Forecast, 1/12/2006

PXI Industry Adoption – Electronics Industry Electronic Business 300 – The Rankings 9 of the 10 top Contract Manufacturers use PXI 17 of the 20 top Electronic Businesses use PXI PXI has seen wide industry adoption, which is especially evident when looking at the top electronics industry businesses and contract electronic manufacturers. In fact, PXI is used by 9 of the top 10 contract manufacturers based on data from Electronics Business 9/1/04 and National Instruments PXI usage study. Top 10 contract manufacturers include: Flextronics, Solectron, Sanmina-SCI, Celestica, Jabil Circuits, Elcoteq, Venture, Benchmark Electronics, Universal Scientific Industrial, and Plexus. In addition, PXI is used by 17 of the top 20 Electronics Businesses based on data from Electronics Business 8/1/05 and National Instruments PXI usage study. Electronics Businesses magazine can be found online at http://reed-electronics.com/eb-mag/ Source (Rankings): Electronic Business, August 2005 Source (PXI Use): National Instruments, June 2005

Real-Time Measurements for Tokamak Control with Multicore PC and PXI Systems Dell 2 Quad Core server connected to PXI-1045 (18 slots) by MXI-Express 2-port 8362 - 160MB/s Fusion DAQ system + magnetic probes Magnetic equilibrium/Grad-Shafranov Function parameterisation Multicore processing application

Harvard Research Group Uses NI LabVIEW and PXI to Study Nanowire Growth Application: Developing a highly flexible and compact lock-in amplifier Challenge: Creating a virtual, high-channel-count, lock-in amplifier for nanotechnology research. Products: LabVIEW, Modular Instruments, PXI/CompactPCI Key Benefit: Flexibility to combine multiple PXI modules and instruments into one project. Harvard Research Group Uses NI LabVIEW and PXI to Study Nanowire Growth “The system provides improved cost, smaller dimensions, and more flexibility than its traditional counterpart. NI: $93,100 USD, Traditional: $512,000 USD” Harvard Research Group Uses NI LabVIEW and PXI to Study Nanowire Growth 28 28

Case Study – Freightliner Selects National Instruments LabVIEW and PXI to Verify Truck Assembly Freightliner selected LabVIEW and PXI to verify electrical assembly on its new line of heavy-duty trucks. Freightliner engineers integrated electrical test, machine vision and physical measurements into a system that not only ensures high-quality vehicles but also instructs operators on the correct assembly process. “We set out to design a high-performance test system that would give us the flexibility of a completely off-the-shelf solution. This system delivers on both requirements and the successful development is reflective of the valuable relationships Freightliner enjoys with both external and internal resources.” What: Freightliner is using LabVIEW and PXI to test it’s new line of trucks. Challenge: Developing a system that combines machine vision, electrical test and physical measurements into a single production test system. Solution: Using LabVIEW and PXI to design an open, off-the-shelf system that can be easily expanded for future applications. Why: Freightliner is the largest heavy-duty truck manufacturer in North America and a leading producer of medium-duty trucks and specialized commercial vehicles. This application supports the ETT campaign. Additional Information: Freightliner is a DaimlerChrysler company. The integrator, Wineman Technology, pitched this application to Freightliner at a NITS event and built the prototype in his house. “Using machine vision to verify the assembly of the fuse box goes beyond the industry standard of validating serial fuse continuity,” said Darryn La Zar, vice president of Sales and Marketing at Wineman Technology. “For instance, this solution can detect if a 30 A fuse is in a 5 A slot, which was not possible before.”

Case Study - PSA Peugeot Citroën Simulates Automotive Environments with NI LabWindows™/CVI and PXI PSA is Europe’s second-leading automotive manufacturer, with strong growth in Latin America and China The company developed a modular test system for prototype vehicles that reduced functional test by half over traditional instruments “By using an approach based on National Instruments LabVIEW software, integrating our simulation models with real-world I/O, we cut development time nearly in half, to 14 days. This is a key element to consider when reducing vehicle time-to-market.” What: One of Europe’s largest automobile manufacturers is using LabWindows too validate engine control without a prototype. Challenge: Performing functional validations without a prototype vehicle, but with similar electronic topology. Solution: Designing a low-cost, high-performance, and simple modular system using PXI hardware and National Instruments LabWindows/CVI application development environment. Why: PSA had to quickly implement validation tools with an industry-standard programming software that was easy to maintain and had a flexible configuration. It was also necessary to find simple, low-cost, high-performance tools. This supports the VI campaign. Additional Information: PSA chose a modular PXI system, which included an 8-slot chassis connected to isolated and conditioned signals to protect the NI modules. The chassis, which can be driven by an external PC via the National Instruments PXI-8330 or embedded in an NI PXI-8187 controller, contains a PXI-6040 multifunction data acquisition module; the PXI-6713 and PXI-6704 analog output modules; the PXI-6602, PXI-6624, and PXI-6527/28 digital I/O modules; and two PXI-8461 CAN interface modules. In some configurations, the application handles up to 18 analog inputs, 32 analog outputs, 24 digital inputs, 24 digital outputs, 10 counter inputs, and 4 counter outputs.

Testing a Multitone Transceiver with PXI and NI LabVIEW Application: Use the NI PXI signal generation and digitizer hardware and the National Instruments LabVIEW Real-Time Module to provide hardware and software platforms for the physical layer of a real-time communications system. Challenge: Prototype the physical layer of a communications systems to rapidly evaluate system design tradeoffs. Products: LabVIEW RT, PXI and Modular Instruments Key Benefit: Time savings, easy-to-make GUI “The LabVIEW Real-Time Module and the PXI hardware allowed us to avoid time-consuming embedded programming and analog circuit design.” Submitted paperr 31 31