The RTOS Motto: On Time And On Budget

The RTOS Motto: On Time And On Budget
But is an RTOS always necessary? The answer is application-specific, so understanding what one will deliver is key to determining whether it becomes a requirement or an extravagance.
In general, an RTOS can be used anywhere a non-RTOS is employed. However, it’s rare to find an operating system with a matching RTOS that has exactly the same application programming interface (API). Many of them, though, embed an RTOS within a conventional operating system. For example, Lynux- Works LynxOS and Bluecat Linux share a Linux API. LynxOS is a hard RTOS, while Bluecat inherits its base from Linux.
Linux continues to improve its real-time performance, but its worst-case interrupt latency still doesn’t meet what would be considered hard real time for an RTOS. It all comes down to quality of service (QoS). Platforms like RTLinux Free augment Linux, providing hard real-time class QoS.
It’s important to note that this type of addition often incorporates an RTOS programming environment that’s distinct from the original operating system. An RTOS is typically small compared to a conventional desktop or server OS. They often target more smaller, resource-constrained microcontrollers. For instance, CMX’s CMX-RTX and CMX-Tiny+ can run on 8-bit MCUs up through 64-bit processors.
The increased power and memory capacity of 8-bit processors is making an RTOS more desirable for these platforms. But, an OS or RTOS is usually a requirement in 16-bit platforms and up with RTOS products like Express Logic’s ThreadX, Wind River’s VxWorks, Micrium’s uCOS-II, and Green Hills Software’s velOSity being common selections. Depending on requirements, MontaVista’s Linux meets 16- and 32-bit platform requirements in the low microsecond range.
THE RTOS CORE: SCHEDULING AND PARTITIONING
Most programmers aren’t familiar with RTOS constraints and requirements. Most usually opt for an RTOS due to its performance. Most RTOS products are small and fast, yet an RTOS also adds consistency. Beyond the fact that an RTOS gets the job done quickly, it can guarantee a job will get done.
In many applications, a late result can be catastrophic. Thus, a poor result within the proper timeframe is preferable. These applications are generally called hard real-time systems. Hard real time doesn’t indicate how fast the system may be or how quickly a system may respond. Rather, it refers to how reliably a system can meet the specified requirements.
A hard real-time system may have a fixed cycle time of one minute with a response time of one second. In theory, it’s something almost any operating system could handle. This isn’t always the case, though, as anyone can attest to when waiting for a desktop application to respond within a minute.
Hard real-time systems typically have shorter cycle times and tighter response requirements. Faster processors always help, and multicore platforms can improve response time, too. The trick for developers is to match system requirements to the hardware and software, hence the importance of an RTOS in embedded applications.
An RTOS can implement a range of scheduling policies, and the application will often restrict a programmer’s choices (see the table). Non-preemptive scheduling is trivial to implement but useful in some applications. On the other hand, non-preemptive scheduling within a task can be implemented on top of a preemptive system.
Non-preemptive should not be overlooked, especially in light of new multicore processors. Here, hardware may be tuned to handle an event-based operation in which a thread will wait for an external event to occur. This approach is usually unsuitable for a single-core processor handling multiple threads. On multicore systems with many cores, though, it’s often typical to dedicate one core to handle one peripheral. It then makes sense to have that core idle while waiting for an event to occur.
As a result, preemptive, interrupt-driven RTOS architectures make up the majority of platforms deployed. These platforms have a range of requirements, issues, and solutions (see the figure). Interrupt latency is always an issue, although hardware— multiple register sets, hardware scheduling and task switching, and hierarchical priority interrupt systems—can significantly reduce this overhead.
Several issues coincide with preemption. Most are timing-related, like race conditions, deadlock, starvation, and priority inversion, which occurs when a low-priority task A owns a synchronization resource of a higher-priority task B, and a task C with priority higher than A is running.
Without a feature like priority ceilings, task C can prevent task A and C from running. A priority-ceiling feature changes the priority of task A to that of task C, allowing it to run and eventually release the resource needed by C. At this point, task A’s priority returns to normal and task C can run.
The other timing-related issues, which the programmer must address, are often the sources of bugs that are difficult to locate and correct. Trace tools become valuable assets in locating these kinds of bugs, since symptoms such as blocked tasks are the only indication of the problem

HAMANN AG assures

HAMANN AG assures

      
      The Spare Part Division of HAMANN AG assures, that all customers around the globe will be    
      supplied with spare parts for their HAMANN Plants, even if the plant was delivered many years ago.

      All orders will be processed immediately and will be delivered with the highest priority without any delay. 
 
      Virtually every spare part is available on stock.  

 

 
 
 
 
 

Fluke Corporation

Fluke Biomedical to unveil new x-ray quality assurance technology at RSNA
CLEVELAND, OHIO – Fluke Biomedical announced today plans to unveil new additions to their x-ray maintenance, calibration, and quality assurance tool platform during the RSNA tradeshow in Chicago on November 29 – December 4, 2009.  Sources close to the project report a new dosimeter is in the works for the wireless TNT 12000 X-Ray Test platform, as well as integrated mA/mAs measurement capability. 

Offering customized bundles to ensure you can meet your QA test protocol without paying for extras you don’t need, the TNT 12000 X-Ray Test Tools provide an unbeatable combination of accuracy, reliability, and ease of use.  Now with choice of all-in-one detector, dosimeter, integral mA/mAs, and handheld display or user’s own laptop interface, the TNT 12000 X-Ray Test Tools platform is anticipated to prove a new industry best for quality, speed, and customer-focused design. 

Visit Fluke Biomedical at RSNA, booth # 4665, for the official unveiling of this innovative new technology.  For more information about the RSNA event, visit . 


About Fluke Biomedical
Fluke Biomedical, a division of Fluke Corporation, is a manufacturer of quality biomedical test and simulation products and a provider of the latest medical imaging and oncology quality-assurance solutions for regulatory compliance.

About Fluke Corporation
Fluke Corporation is the world leader in compact, professional electronic test tools. Fluke customers are technicians, engineers, electricians and metrologists who install, troubleshoot and manage industrial electrical, biomedical and electronic equipment and calibration processes for quality control.

specializing ln portable equipment

The UMX-2 Underwater gauge is the latest addition to the Dakota product range. Fully equipped with our DSP platform using FPGA technology, it's extremely versatile for all those offshore inspections. Our enclosure is extremely durable, with a maximum depth rating of 1000ft (300m), and offers the use of both Dual & Single Membrane transducers to accomodate your application requirements. The features include: auto probe zero, auto probe recognition, and multiple measurement mode options.

Our Dual Element modes (corrosion inspections) include: Pulse-Echo (pits & flaws), Echo-Echo (thru-paint) & Pulse-Echo w/coating (combo). Our Single Membrane probe option uses a Triple-Echo (TCG) mode for coated and uncoated general applications. While not suitable for blind surface corossion inspections, this option offers good linearity for general purpose applications.

The calibration section contains 8 common pre-programmed material types and 1 custom user programable option. Connect the UMX-2 to your PC, and program it with our DakView3 utility software.

Our UMX-2 stores up to 5,000 readings in a variety of configurations. The file structure options include: sequential with auto identifier and alpha numeric grid formats. Every measurement stored also saves a copy of the UMX-2 current settings, along with an A-Scan waveform graphic.

Take a good look at the feature set...and, of course, our price tag!

 
Welcome to the Dakota Ultrasonics website!

We are a manufacturer of industrial ultrasonic testing equipment most commonly used in the petrochemical, aerospace, automotive, and other generally related industries. The pages that follow will provide you with general information regarding our products. If you have any questions, need technical support, or have a request for custom items, please contact us at your leisure using the information provided on this site.

Our products are commonly used to determine the thickness of a variety of materials by making contact with only one side of the material being tested. They have the ability to detect very fine pits, flaws, and porosity in materials without having to destroy the material or parts being tested. This is done by converting the transit time of a sound wave, sent into and reflecting back from a defect or opposite surface in the test material, into a length measurement. This technique uses principles similar to that of sonar.

We also manufacture a line of ultrasonic bolting equipment that very accurately measures the stress, elongation, and load in threaded fasteners. These products are typically used in critical bolting applications where extreme accuracy is needed. If you have any specific or specialized bolting applications in mind, be sure to contact us to discuss your requirements in detail.

Enjoy!

Thousands of Sensors shipped a month. Learn Why.

Easy to use sensors, that provide stable range readings, have caused our ultrasonic rangefinders to be the sensor of choice for Original Equipment Manufacturers (OEM's), Professional Engineers, Educators and Hobbyists alike.  To check out our full line of products click to learn about our Ultrasonic Sensors Thousands of Sensors shipped a month. Learn Why. Reliable Sensors - Incredibly small packages - Ultra Low Power Consumption - Indoor sensors & Robust Outdoor (IP67) sensors - Calibrated Beam patterns - Low cost - Without Compromising Performance - This is part of why...        LV Products     XL Products   WRC Products       WR Products High Performance, Low Cost Ultrasonic Rangefinders Our standard products (and customer requested variations) are considered to be the sensor of choice for many applications such as: people proximity detection in automated booth & kiosks, remote monitoring stations, First Robotics autonomous, educational curriculums, and hobby sensing and robotics projects.  Our standard products, or a custom variation, can be used for your next ultrasonic sensor application. Sensor Selection Guide For help in selecting a sensor try our Sensor Selection Guide To purchase one of our products visit our BUY NOW page or you can always check out one of our Distributors  OEM's are encouraged to e-mail for volume pricing. For more information our datasheets, application notes, and MTBF reliability demonstration are available in our list of Downloads    Questions or comments... please email us at info@maxbotix.com To place an order by phone, please call during our preferred business hours of 9:00am - 3:00pm CST, Monday through Thursday,  9:00am - 12:00pm Friday. Orders placed after 3:00pm Thursday typically ship the following Monday. MaxBotix® Inc. 7594 County Road 143 Brainerd, MN 56401 Phone: 00-1-218-454-0766 Fax: 00-1-218-454-0768 The names MaxBotix, MaxSonar, EZ0, EZ1, EZ2, EZ3, EZ4, AE0, AE1,AE2, AE3, AE4 and WR1 are trademarks of MaxBotix Inc. All other trademarks mentioned herein are the property of their respective company.

European Stocks Increase for Second Week; Banks, Danisco, ARM Shares Gain

European stocks advanced for a second week as investors speculated that the European Union will increase its efforts to contain the region’s debt crisis.

Banking shares posted their best weekly performance in six months. Danisco A/S jumped 25 percent as DuPont Co. agreed to buy the company. Provident Financial Plc surged 13 percent after saying 2010 earnings may exceed analysts’ projections.

The benchmark Stoxx Europe 600 Index gained 1 percent this week as Portugal, Spain and Italycompleted debt sales. The gauge rallied 8.6 percent in 2010 as the European Union bailed out Greece and Ireland, companies reported increased profits and the Federal Reserve unveiled $600 billion of additional bond purchases to support the economy.

“The first test of the ability of the euro-area peripheral countries to secure financing on the market has been passed,” a team of economists at Intesa Sanpaolo SpA, including Luca Mezzomo and Paolo Mameli, wrote in a report. “The fears over the outcome of the January auctions in Portugal, Spain and Italy proved unfounded.”

Portugal sold 599 million euros ($800.1 million) of 10-year bonds at an average yield of 6.716 percent this week, compared with a yield of 6.806 percent at the previous sale on Nov. 10.

In Spain, demand and borrowing costs increased at a 3 billion-euro sale of five-year notes. Investors bid for 2.1 times the securities on offer, up from 1.6 the last time Spain sold the debt on Nov. 4. The average yield climbed to 4.542 percent from 3.576 percent.

Japanese, Chinese Support

Japanese Finance Minister Yoshihiko Noda said “it’s appropriate” for his nation to buy bonds issued by Europe’s financial-aid funds later this month. China has also voiced support for Europe, with Vice Premier Li Keqiang last week expressing confidence in Spain’s financial markets and pledging to buy more of that country’s debt.

EU officials are trying to forge a “comprehensive” plan to contain the currency area’s sovereign-debt crisis, Economic and Monetary Commissioner Olli Rehn said this week. German Finance Minister Wolfgang Schaeuble said EU member states will assemble a “comprehensive package” to tackle the sovereign- debt crisis by March.

European stocks trimmed some of their gains as the People’s Bank of China told the country’s major lenders to increase their reserve ratios by 50 basis points from Jan. 20. China raised its benchmark interest rates on Christmas Day to rein in liquidity.

German, Euro-Area Inflation

Separately, inflation in Germany, Europe’s largest economy, accelerated to the fastest pace in more than two years in December, data from the Federal Statistics Office in Wiesbaden showed. European Central Bank council member Axel Weber said euro-area inflation risks “could well move to the upside” as the region’s economic outlook has improved markedly.

Euro-area inflation accelerated to 2.2 percent in December, exceeding the ECB’s 2 percent limit for the first time in more than two years.

The central bank kept interest rates at a record low as ECB President Jean-Claude Trichet said inflation pressures in the euro region have picked up. The Governing Council set the benchmark rate at 1 percent for the 21st month, as predicted by all 53 economists in a Bloomberg News survey. The Bank of England also kept its key rate unchanged at 0.5 percent.

National benchmark indexes rose in 15 of Europe’s 18 western markets. France’s CAC 40 Index gained 3 percent, the U.K.’s FTSE 100 Index rose 0.3 percent, while Germany’s DAX Index advanced 1.8 percent. Spain’s IBEX 35 Index jumped 8.6 percent, while Italy’s FTSE MIB Index surged 4.5 percent.

Europe’s Banks

European banking shares jumped 6.2 percent this week, their biggest weekly gain since July and the best performance among 19 industry groups in the Stoxx 600. Banco Santander SA and Banco Bilbao Vizcaya Argentaria SA, Spain’s biggest banks, jumped 13 percent and 16 percent, respectively. UniCredit SpA advanced 12 percent. Banco Comercial Portugues SA advanced 5.4 percent, the stock’s first weekly gain in more than a month.

Danisco soared 25 percent as DuPont agreed to acquire the world’s largest maker of food ingredients for $5.8 billion, adding the production of enzymes used in food and biofuels to its range of businesses.

ARM Holdings Plc rallied 15 percent as Compal Electronics Inc., the world’s second-largest maker of notebook computers, forecast that 90 percent of the 3.8 million tablet devices it ships this year will use chips from ARM alongside Google Inc.’s Android operating system.

Provident Financial, Sky

Provident Financial, the U.K.’s biggest listed subprime lender, jumped 13 percent, the largest weekly gain in 2 1/2 years.

“The group had a strong finish to 2010 and expects to report results slightly ahead of market expectations,” Chief Executive Officer Peter Crook said. The company will report earnings on March 1.

Sky Deutschland AG rose 25 percent after the company reached an agreement with News Corp. to raise 400 million euros in financing, more than the 340 million euros it had previously sought. Sky Deutschland also predicted that 2011 earnings before interest, taxes, depreciation and amortization will be “significantly better than 2010, but will remain negative.”

Oriflame Cosmetics SA led falling shares in the Stoxx 600, losing 11 percent, as the maker of cosmetics said fourth-quarter sales were “slightly weaker than expected.”

Tesco Plc fell 5.6 percent after Britain’s biggest retailer reported holiday sales growth that lagged behind its competitors, saying that snow kept Britons from visiting out-of- town supermarkets.

Retail stocks lost 1.3 percent this week.

-- With assistance from Francesca Cinelli in Milan. Editors: Will Hadfield, Andrew Rummer

Fed Officials Say Strengthening Economy Doesn't Alter Bond-Purchase Plans

Federal Reserve policy makers said the central bank needs to bring down unemployment by pressing on with record monetary stimulus even as the economy shows signs of gaining strength.

Boston Fed President Eric Rosengren predicted in a speech yesterday that under current policy, it will take several years to reach full employment and an inflation rate of about 2 percent. Governor Daniel Tarullo told CNBC that “I haven’t seen anything which would warrant a reconsideration” of the Fed’s plans to buy $600 billion of Treasuries through June.

The comments capped a week of remarks by central bankers indicating no change to a policy that has prompted the strongest political backlash in three decades. Fed Bank of St. Louis President James Bullard said in an interview this week that while the U.S. growth outlook has improved after a “strong” holiday shopping season, he wants to see more evidence before considering reducing or slowing the stimulus.

Richmond Fed President Jeffrey Lacker predicted the program will come under greater scrutiny by policy makers as growth quickens. “While the outlook may not have improved enough yet to warrant adjusting our purchase plans in the near-term, I anticipate earnest re-evaluation as economic developments unfold in the months ahead,” Lacker said yesterday in a speech in Richmond, Virginia. Fed officials plan to meet in Washington on Jan. 25-26.

Politicians such as Representative Ron Paul, a Texas Republican who has advocated abolishing the Fed, have said the central bank’s so-called quantitative easing plan risks spurring inflation.

Industrial Production

Reports yesterday on retail sales and industrial production supported forecasts for quickening growth this year that may boost demand for products ranging from Ford Motor Co. cars to Apple Inc. iPads.

Purchases climbed 0.6 percent, capping the biggest annual increase in more than a decade, Commerce Department figures showed. Output at factories, mines and utilities increased 0.8 percent, the most in five months, according to data from the Federal Reserve.

Stocks rose, with the Standard & Poor’s 500 Index increasing 0.7 percent to 1,293.24 in New York trading. The yield on 10-year Treasuries increased three basis points 3.33 percent, after earlier falling to 3.25 percent, the lowest level since Dec. 20. It was little changed for the week.

Lacker and Rosengren predicted the economy will expand 3.5 percent to 4 percent this year. Growth won’t exceed 4 percent because the housing market’s recovery is likely to be weaker than usual, given the tightening of lending standards and high vacancy rates, Rosengren said.

No Boost to Recovery

“If housing-related growth is not going to boost the recovery this time around, we may need policy -- particularly monetary policy -- to continue playing a stimulative role,” said Rosengren, who doesn’t vote on monetary policy this year.

Growth of 4 percent would still leave the unemployment rate close to 9 percent at the end of 2011, a level that’s “far above anyone’s estimate of full employment,” Rosengren said.

The jobless rate has held at 9.4 percent or higher since May 2009. Rosengren said it will probably take at least four years to return to full employment.

“Until we get to the point where jobs are being created at a consistent and continuing pace that will bring down unemployment, there is going to be an inherent lack of robustness in the economy,” said Tarullo, 58, who was President Barack Obama’s first appointee to the central bank in January 2009. He said the economy has “decidedly improved.”

Household Debt

Lacker said he expects the economy to improve further because of a firming labor market and reduced household debt.

“Given these stronger fundamentals, it’s not a stretch to project robust growth in consumer spending this year,” Lacker said.

“Even with a relatively robust recovery, it will take several years before we attain full employment and an inflation rate close to a long-run expectation of 2 percent,” Rosengren said yesterday in a speech in Mashantucket, Connecticut. “The current level of accommodation from monetary and fiscal policy is appropriate.”

At their last meeting, some officials on the Fed’s Open Market Committee said they had a “fairly high threshold for making changes” to the Fed’s $600 billion round of purchases, according to minutes of the gathering.

Fed Chairman Ben S. Bernanke said this week during a panel discussion that “we see the economy strengthening,” adding that “you’re not going to reduce unemployment at the pace that we’d like it to.”

Scaling Back

Lacker told reporters after his speech that “it’s not inconceivable to me that we would find growth coming in strong enough in the next couple of months to warrant scaling back on the program.”

Inflation will probably rise to between 1.5 percent and 2 percent this year, Lacker said. Fed presidents rotate voting on monetary policy with Lacker voting next year.

“The downward trend in inflation during the recession had many commentators warning of the possibility of outright deflation,” he said. “At this point, I think the risk of deflation is negligible.”

Still, “the lesson of the ‘70s at this time in the business cycle is we need to be careful,” Lacker said to reporters. “For the next couple of years we need to be really careful about the potential for inflation to accelerate if we’re not vigilant enough about reacting.”