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Farmers, Technology and Freedom of Choice: A Tale of Two Satyagrahas

This is the 23rd installment of The Rationalist, my column for the Times of India.

I had a strange dream last night. I dreamt that the government had passed a law that made using laptops illegal. I would have to write this column by hand. I would also have to leave my home in Mumbai to deliver it in person to my editor in Delhi. I woke up trembling and angry – and realised how Indian farmers feel every single day of their lives.

My column today is a tale of two satyagrahas. Both involve farmers, technology and the freedom of choice. One of them began this month – but first, let us go back to the turn of the millennium.

As the 1990s came to an end, cotton farmers across India were in distress. Pests known as bollworms were ravaging crops across the country. Farmers had to use increasing amounts of pesticide to keep them at bay. The costs of the pesticide and the amount of labour involved made it unviable – and often, the crops would fail anyway.

Then, technology came to the rescue. The farmers heard of Bt Cotton, a genetically modified type of cotton that kept these pests away, and was being used around the world. But they were illegal in India, even though no bad effects had ever been recorded. Well, who cares about ‘illegal’ when it is a matter of life and death?

Farmers in Gujarat got hold of Bt Cotton seeds from the black market and planted them. You’ll never guess what happened next. As 2002 began, all cotton crops in Gujarat failed – except the 10,000 hectares that had Bt Cotton. The government did not care about the failed crops. They cared about the ‘illegal’ ones. They ordered all the Bt Cotton crops to be destroyed.

It was time for a satyagraha – and not just in Gujarat. The late Sharad Joshi, leader of the Shetkari Sanghatana in Maharashtra, took around 10,000 farmers to Gujarat to stand with their fellows there. They sat in the fields of Bt Cotton and basically said, ‘Over our dead bodies.’ ¬Joshi’s point was simple: all other citizens of India have access to the latest technology from all over. They are all empowered with choice. Why should farmers be held back?

The satyagraha was successful. The ban on Bt Cotton was lifted.

There are three things I would like to point out here. One, the lifting of the ban transformed cotton farming in India. Over 90% of Indian farmers now use Bt Cotton. India has become the world’s largest producer of cotton, moving ahead of China. According to agriculture expert Ashok Gulati, India has gained US$ 67 billion in the years since from higher exports and import savings because of Bt Cotton. Most importantly, cotton farmers’ incomes have doubled.

Two, GMO crops have become standard across the world. Around 190 million hectares of GMO crops have been planted worldwide, and GMO foods are accepted in 67 countries. The humanitarian benefits have been massive: Golden Rice, a variety of rice packed with minerals and vitamins, has prevented blindness in countless new-born kids since it was introduced in the Philippines.

Three, despite the fear-mongering of some NGOs, whose existence depends on alarmism, the science behind GMO is settled. No harmful side effects have been noted in all these years, and millions of lives impacted positively. A couple of years ago, over 100 Nobel Laureates signed a petition asserting that GMO foods were safe, and blasting anti-science NGOs that stood in the way of progress. There is scientific consensus on this.

The science may be settled, but the politics is not. The government still bans some types of GMO seeds, such as Bt Brinjal, which was developed by an Indian company called Mahyco, and used successfully in Bangladesh. More crucially, a variety called HT Bt Cotton, which fights weeds, is also banned. Weeding takes up to 15% of a farmer’s time, and often makes farming unviable. Farmers across the world use this variant – 60% of global cotton crops are HT Bt. Indian farmers are so desperate for it that they choose to break the law and buy expensive seeds from the black market – but the government is cracking down. A farmer in Haryana had his crop destroyed by the government in May.

On June 10 this year, a farmer named Lalit Bahale in the Akola District of Maharashtra kicked off a satyagraha by planting banned seeds of HT Bt Cotton and Bt Brinjal. He was soon joined by thousands of farmers. Far from our urban eyes, a heroic fight has begun. Our farmers, already victimised and oppressed by a predatory government in countless ways, are fighting for their right to take charge of their lives.

As this brave struggle unfolds, I am left with a troubling question: All those satyagrahas of the past by our great freedom fighters, what were they for, if all they got us was independence and not freedom?

The India Uncut Blog © 2010 Amit Varma. All rights reserved.
Follow me on Twitter.




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For this Brave New World of cricket, we have IPL and England to thank

This is the 24th installment of The Rationalist, my column for the Times of India.

Back in the last decade, I was a cricket journalist for a few years. Then, around 12 years ago, I quit. I was jaded as hell. Every game seemed like déjà vu, nothing new, just another round on the treadmill. Although I would remember her fondly, I thought me and cricket were done.

And then I fell in love again. Cricket has changed in the last few years in glorious ways. There have been new ways of thinking about the game. There have been new ways of playing the game. Every season, new kinds of drama form, new nuances spring up into sight. This is true even of what had once seemed the dullest form of the game, one-day cricket. We are entering into a brave new world, and the team leading us there is England. No matter what happens in the World Cup final today – a single game involves a huge amount of luck – this England side are extraordinary. They are the bridge between eras, leading us into a Golden Age of Cricket.

I know that sounds hyperbolic, so let me stun you further by saying that I give the IPL credit for this. And now, having woken up you up with such a jolt on this lovely Sunday morning, let me explain.

Twenty20 cricket changed the game in two fundamental ways. Both ended up changing one-day cricket. The first was strategy.

When the first T20 games took place, teams applied an ODI template to innings-building: pinch-hit, build, slog. But this was not an optimal approach. In ODIs, teams have 11 players over 50 overs. In T20s, they have 11 players over 20 overs. The equation between resources and constraints is different. This means that the cost of a wicket goes down, and the cost of a dot ball goes up. Critically, it means that the value of aggression rises. A team need not follow the ODI template. In some instances, attacking for all 20 overs – or as I call it, ‘frontloading’ – may be optimal.

West Indies won the T20 World Cup in 2016 by doing just this, and England played similarly. And some sides began to realise was that they had been underestimating the value of aggression in one-day cricket as well.

The second fundamental way in which T20 cricket changed cricket was in terms of skills. The IPL and other leagues brought big money into the game. This changed incentives for budding cricketers. Relatively few people break into Test or ODI cricket, and play for their countries. A much wider pool can aspire to play T20 cricket – which also provides much more money. So it makes sense to spend the hundreds of hours you are in the nets honing T20 skills rather than Test match skills. Go to any nets practice, and you will find many more kids practising innovative aggressive strokes than playing the forward defensive.

As a result, batsmen today have a wider array of attacking strokes than earlier generations. Because every run counts more in T20 cricket, the standard of fielding has also shot up. And bowlers have also reacted to this by expanding their arsenal of tricks. Everyone has had to lift their game.

In one-day cricket, thus, two things have happened. One, there is better strategic understanding about the value of aggression. Two, batsmen are better equipped to act on the aggressive imperative. The game has continued to evolve.

Bowlers have reacted to this with greater aggression on their part, and this ongoing dialogue has been fascinating. The cricket writer Gideon Haigh once told me on my podcast that the 2015 World Cup featured a battle between T20 batting and Test match bowling.

This England team is the high watermark so far. Their aggression does not come from slogging. They bat with a combination of intent and skills that allows them to coast at 6-an-over, without needing to take too many risks. In normal conditions, thus, they can coast to 300 – any hitting they do beyond that is the bonus that takes them to 350 or 400. It’s a whole new level, illustrated by the fact that at one point a few days ago, they had seven consecutive scores of 300 to their name. Look at their scores over the last few years, in fact, and it is clear that this is the greatest batting side in the history of one-day cricket – by a margin.

There have been stumbles in this World Cup, but in the bigger picture, those are outliers. If England have a bad day in the final and New Zealand play their A-game, England might even lose today. But if Captain Morgan’s men play their A-game, they will coast to victory. New Zealand does not have those gears. No other team in the world does – for now.

But one day, they will all have to learn to play like this.

The India Uncut Blog © 2010 Amit Varma. All rights reserved.
Follow me on Twitter.




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Virtuoso Studio: Simplified Review of Operating Point Parameter Values

Read on to know about the Operating Point Parameters Summary window that gives you a one-stop view of the categorized and tabulated details on all operating point parameters in your design. This window improves your review cycle with its many benefits.(read more)



  • Analog Design Environment
  • Operating point summary window
  • Virtuoso Studio
  • Operating Point Information
  • Virtuoso Analog Design Environment
  • Custom IC Design
  • Virtuoso ADE Explorer
  • Virtuoso ADE Assembler
  • IC23.1

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How Do You Ensure the Reliability of Your Design in Virtuoso Studio?

Designers have long recognized the need to analyze the reliability of ICs. Two commonly used approaches for performing reliability analysis include calculating the change in device degradation and relying on safe operating checks in circuit simulators. 

With the advent of the ever-increasing use of ICs in mission-critical applications, the need for reliable reliability analysis has become of paramount importance. Over the years, you have been using reliability analysis in Virtuoso ADE Assembler and Virtuoso ADE Explorer to measure and review aging effects, such as device characteristic degradations, model parameter changes, self-heating effects, and so on.

Reliability analysis can be performed using two modes: Spectre native and RelXpert. The reliability analysis analyzes the effect of time on circuit performance drift and predicts the reliability of designs in terms of performance. In ADE Assembler, you can run the reliability simulation for fresh test (when time is zero), stress test (to generate degradation data), and aged test (at specific intervals, such as one year, three years, or 10 years). In the stress test, extreme environmental conditions are used to stress devices before aging analysis.

The following figure shows the reliability simulation flow.

 

 

The Reliability Options form has the following four tabs: 

  • Basic: Enables you to specify analysis type, aging options, start and stop time of reliability simulation, and options related to device masking, degradation ratio, and lifetime calculation. 
  • Modeling: Enables you to choose the modeling type you want to use during reliability simulation. 
  • Degradation: Enables you to specify the options to print device and subcircuit degradation information into a .bt0 file. 
  • Output: Enables you to specify the degradation reports to be generated and methods to filter degradation results in the reports.

While the Basic and the Output tabs are used by design engineers, the Modeling and the Degradation tabs are primarily used by model developers.

 

Reviewing degradation reports in text or XML formats can be a tiresome exercise because degradation data can be large and can contain a large number of instances due to advanced technology nodes and post-layout simulations. For you to work effectively and interactively with these reports, the new reliability report is based on the SQLite database, which adds the benefit of improved performance and capabilities of sorting and filtering reliability data using SQLite operators.

 

As they say, watching this in action might help you more than reading about it, so please take a look at our Training Bytes video channel, which offers many helpful videos on how to run Reliability Analysis in Virtuoso Studio.

All the related videos are linked together in a channel so that you can easily access and watch as many as you like.

Reliability Analysis in Virtuoso Studio

 

Want to Learn More?

For lab instructions and a downloadable design, enroll for the online training courses of your interest on

Reliability Analysis in Virtuoso Studio vIC23.1 (Online)

 Training is also available as "Blended" or "live" class.

Digital Badge Available

You can become Cadence Certified once you complete the course (s) and share your knowledge and certifications on social media channels. Go straight to the course exam at the Learning and Support Portal.

Note: Some of the above links are accessible only to Cadence customers who have a valid login ID for the Cadence Learning and Support Portal.

Do You Have Access to the Cadence Support Portal?

If not, follow the steps below to create your account.

  • On the Cadence Support portal, select Register Now and provide the requested information on the Registration page.
  • You will need an email address and host ID in order to sign up.
  • If you need help with registration, contact support@cadence.com.

To stay up-to-date with the latest news and information about Cadence training and webinars, subscribe to the Cadence Training emails.

If you have questions about courses, schedules, online, public, or live onsite training, reach out to us at Cadence Training.

Related Resources

  Training Bytes (Videos)

Virtuoso ADE Explorer Graphical User Interface

What is the need for Reliability Analysis? (Video)

  Blogs

Come Join Us and Learn from the Cadence Training Offerings

It’s the Digital Era; Why Not Showcase Your Brand Through a Digital Badge!

  Online Course

Reliability Analysis in Virtuoso Studio vIC23.1 (Online)

 

About Knowledge Booster Training Bytes

Knowledge Booster Training Bytes is an online journal that relays information about Cadence Training videos, online courses, and upcoming webinars that are available in the Learning section of the Cadence Learning and Support portal. This blog category brings you direct links to these videos, courses, and other related material on a regular basis.

Niyati Singh

On behalf of the Cadence Training team





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Virtuoso Studio: How Do You Name Simulation Histories in Virtuoso ADE Assembler?

This blog describes an efficient way to name the histories saved by the simulation runs in Virtuoso ADE Assembler.(read more)




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Doc Assistant A-Z: Making the Most of the Cadence Cloud-Based Help Viewer: Pt. 2

At a bustling Cadence event, we met Adrian, an intern at a startup who immerses himself in Cadence tools for his research and work.

Adrian was enthusiastic about the innovative technologies at his disposal but faced a significant challenge: internet access was limited to a single machine for new joiners, forcing interns to wait in line for their turn to use online resources.

Adrian's excitement soared when he discovered a game-changing solution: Doc Assistant. The cloud-based help viewer, Doc Assistant, ships with all Cadence tools, enabling Adrian to access help resources offline from any machine equipped with the software. This meant Adrian could continue his research and work seamlessly, irrespective of internet availability!

Meeting Cadence users and customers at such events has given us the opportunity to showcase how they can benefit from the diverse features that Doc Assistant offers.

With that note, welcome back to our Doc Assistant A-Z blog series! In Part 1, we explored key features and benefits that our innovative viewer brings to the table. Today, in Part 2, we'll dive deeper into the advanced functionalities and customization options that make Doc Assistant indispensable for its users.

Whether you're looking to streamline your workflow or enhance your user experience, this blog will provide the insights you need to fully leverage the capabilities of our documentation viewer. Let’s get started!

What Makes Doc Assistant Stand Out?

Here are a few (more) cool features of Doc Assistant!

History and Bookmarks: Want to refer to the topic you read last week? Of course, you can! Doc Assistant stores your browsing activity as History. You can also bookmark topics and revisit them later.

Indexing Capabilities: Looking for seamless search capabilities? The advanced indexing capabilities of Doc Assistant enhance the accessibility and manageability of documents. Doc Assistant automatically creates a search index if it is missing or broken.

Jump Links: Worried about scrolling through lengthy topics? Fret no more! Use the jump links in each topic to quickly navigate to different sections within the same topic or across topics. Jump links reduce the need for excessive scrolling and let you access relevant content swiftly.

Just-in-Time Notifications: Looking for alerts and messages? That’s supported. Doc Assistant displays notifications about important events, including errors, warnings, information, and success messages.

Keyword-Based Search Suggestions: You somewhat know your search keyword, but not quite sure? No worries. Just start typing what you know. Keyword and page suggestions are displayed dynamically as you type, providing a more sophisticated and intuitive search experience.

Library-Switch Support: Want to view documents from other libraries? Doc Assistant, by default, displays documents for the currently active release in your machine. You can access documents from other releases by configuring the associated documentation libraries.

Multimedia Support: Want to view product demos? Multimedia support in Doc Assistant lets you play videos, listen to audio, and view images without opening any external application.

Navigation Made Easy: Worried that you’ll get lost in an infinite doc loop? Not at all. The intuitive navigation controls in Doc Assistant are designed to provide you with a fluid and efficient experience. The Doc Assistant user interface is clean and logically organized, with easy-to-access documentation links.

That's not all. We have more coming your way. Until next time, take care and stay tuned for our next edition!

Want to Know More?

Here's a video about Doc Assistant
Visit the Doc Assistant web page
Read the Doc Assistant FAQ document

For any questions or general feedback, write to docassistant.support@cadence.com.

Subscribe to receive email notifications about our latest Custom IC Design blog posts.

Happy reading!

-Priya Sriram, on behalf of the Doc Assistant Team




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Knowledge Booster Training Bytes - Writing Physical Verification Language Rules

Have you ever wanted to write a DRC rule deck to check for space or width constraints on polygons? Or have you wondered how the multiple lines of an LVS rule deck extract and conduct a comparison between the schematic and layout? Maybe you've been curious about the role of rule deck writers in creating high-quality designs ready for tape-out.

If any of these questions interest you, there is good news: the latest version (v23.1) of the Physical Verification Rules Writer (PVLRW) course is designed to teach you rule deck writing. This free 16-hour online course includes audio and labs designed to make your learning experience comfortable and flexible. Whether you are new to the concept or an experienced CAD/PDK engineer, the course is structured to enhance your rule deck writing skills.

The PVLRW course covers six core modules: Layer Processing, DRC Rules, Layout Extraction, ERC and LVS Rules, Schematic Netlisting, and Coloring Rules. There are also three optional appendix sections. Each module explains relevant rules with syntax, concepts, graphics, examples, and case studies.

This course is based on tool versions PEGASUS231 and Virtuoso Studio IC231.

Pegasus Input and Output

Pegasus is a cloud-ready physical verification signoff solution that enables engineers to support faster delivery of advanced-node integrated circuits (ICs) to market.

Pegasus requires input data in the form of layout geometry, schematic netlists, and rules that direct the tool operation. The rules fall into two categories: those that describe the fabrication process and those that control the job-specific operation.

Pegasus provides log and report files, netlists, databases, and error databases as output.

Overview of Pegasus Rule File

The rule decks written in Physical Verification Language (PVL) work for the Cadence PV signoff tools Pegasus and PVS (Physical Verification System).   

The PVL rules are placed in a file that gets selected in a run from the GUI or the command line, as the user directs. PVL rules may be on separate lines within the file and can also be contained in named rule blocks.

Each line of code starts with a PVL rule that uses prefix type notation. It consists of a keyword followed by options, input layer or variable names, and output layer or variable names.

A rule block has the format of the keyword rule, followed by a rule name you wish to give it, followed by an opening curly brace. You enter the rules you wish to perform, followed by a closing curly brace on the last separate line.

  Sample Rule deck with individual lines of code and rule blocks.

DRC Rules

The first step in a typical Pegasus flow is a Design Rule Check (DRC), which verifies that layout geometries conform to the minimum width, spacing, and other fabrication process rules required by an IC foundry. Each foundry specifies its own process-dependent rules that must be met by the layout design.

There are three types of DRC rules: layer definition rules, layer derivation rules, and DRC design check rules. Layer definition rules identify the layers contained in the input layout database, and layer derivation rules derive additional layers from the original input layers, allowing the tool to test the design against specific foundry requirements using the design check rules.

A sample DRC Rule deck

A layout view displaying the DRC violations

LVS Rules

The Pegasus Layout Versus Schematic (LVS) tool compares the layout netlist with the schematic netlist to check for discrepancies.

There are two essential LVS rule sets: LVS extraction rules and comparison rules. LVS extraction rules help extract drawn devices and connectivity information from the input layout geometry data and outputs into a layout netlist. The LVS extraction rule set also includes the layer definition, derivation, extraction, connectivity, and net listing rules.

LVS comparison rules are associated with comparing the extracted layout netlist to a schematic netlist.

A sample LVS Rule deck. 

TCL, Macros, and Conditional commands

Tcl is supported and used in various Pegasus functionalities, such as Pegasus rule files and Pegasus configurator. Macros are functional templates that are defined once and can be used multiple times in a rule file. Conditional Commands are used to process or skip specific commands in the rule file.

Do You Have Access to the Cadence Support Portal?

If not, follow the steps below to create your account.

  • On the Cadence Support portal, select Register Now and provide the requested information on the Registration page.
  • You will need an email address and host ID to sign up.
  • If you need help with registration, contact support@cadence.com.

To stay up to date with the latest news and information about Cadence training and webinars, subscribe to the Cadence Training emails.

If you have questions about courses, schedules, online, public, or live onsite training, reach out to us at Cadence Training.

For any questions, general feedback, or future blog topic suggestions, please leave a comment.

Related Resources

Product Manuals

Cadence Pegasus Developers Guide

Rapid Adoption Kits     Running Pegasus DRC/LVS/FILL in Batch Mode
Training Byte Videos

What Is the Run Command File?

How to Run PVS-Pegasus Jobs in GUI and Batch modes?

PVS DRC Run From - Setup Rules

What Is PVS/Pegasus Layer Viewer?

PVL Coloring Ruledecks with Docolor and Stitchcolor 

PLV Commands: dfm_property with Primary & Secondary Layer

PVS Quantus QRC Overview 

Online Courses

Pegasus Verification System

PVS (Physical Verification System)

Virtuoso Layout Design Basics

About Knowledge Booster Training Bytes

Knowledge Booster Training Bytes is an online journal that relays information about Cadence Training videos, online courses, and upcoming webinars in the Learning section of the Cadence Learning and Support portal. This blog category brings you direct links to these videos, courses, and other related material on a regular basis. Subscribe to receive email notifications about our latest Custom IC Design blog posts.





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Virtuoso Studio IC 23.1: Using Net Tracer for Design Review

This blog explores how Virtuoso Studio Net Tracer can help you perform a design review.

We’ll use the net connectivity option, which allows the user to get a clean highlighted net. You can use the Net Tracer tool to highlight the nets. You can find the Net Tracer command under the connectivity pulldown menu in the layout window.

Trace manager and the ability to display different islands on the same net with other colors, you can identify and connect the unconnected islands as you wish.

The Net Tracer utility traces the nets in the physical view (layout). The trace is a highlighted net, which is a non-selectable object. The Net Tracer utility is available from Virtuoso Layout Suite XL onwards. You can use this utility based on your specific needs and preferences.

For a better understanding of the Net Tracer feature, let’s see one scenario between the circuit designer and layout engineer for a layout design review.

Circuit designer: Can we go through the routed input nets “inm” and “inp”?

Layout engineer: From the below layout view where they are highlighted using the XL connectivity, today I will use Net Tracer utility for the design review.

Circuit designer: I have never heard of this feature. Let's see how it works.

Layout engineer: Sure, now we turn on the Net Tracer toolbar using the below option.

You see the Net Tracer options form here:

As you can see on my screen, I have opened the layout view and engaged the Net Tracer utility.

Net Tracer allows shapes to be traced on a net in two tracing modes, namely, physical and logical, where shapes on the same net are physically or logically connected.

Physical tracing gathers all the shapes physically connected on the same net.

Logical tracing gathers all the shapes assigned to the same net. It highlights the net as in the source design (schematic). It will highlight shapes on the same net, even if they are isolated shapes that are not physically connected.

For this scenario, let us use physical tracing for input nets “inm” and “inp."

Highlighted nets are shown below:

Net “inm”                    Net “inp”                   Nets “inm” and “inp” 

      

Net Tracer has features like physical and logical tracing, preview, step-by-step mode, ease of tracing a net on a shape out of multiple underlying shapes, and so on.

Let us explore logical tracing for output nets “outm” and “outp”:

Here, you can see how to enable true color and halo before enabling logical tracing to identify the metal route. After enabling the true color halo, enable the logical trace.

Here, I am opening the trace manager to search “outm” and “outp” and click trace. That will trace the particular nets as shown.

Net Tracer has a preview feature, which is helpful in terms of the number of previewed objects. This preview capability hints at how the trace would appear when you create it. This useful feature in Virtuoso Studio highlights both completed and incomplete nets, helping the user better understand the status of the highlighted nets.

Circuit designer: Thanks for the design review. You have done good work. Net Tracer clearly shows both types of tracing, and it was even easy for the circuit designer to understand.

Layout engineer: Let me share the link to the Net Tracer RAK, where other layout engineers can explore many more amazing features of the Net Tracer.

Do You Have Access to the Cadence Support Portal?

If not, follow the steps below to create your account.

  • On the Cadence Support portal, select Register Now and provide the requested information on the Registration page.
  • You will need an email address and host ID to sign up.
  • If you need help with registration, contact support@cadence.com.

To stay up to date with the latest news and information about Cadence training and webinars, subscribe to the Cadence Training emails.

If you have questions about courses, schedules, online, public, or live onsite training, reach out to us at Cadence Training.

For any questions, general feedback, or future blog topic suggestions, please leave a comment.

Become Cadence Certified

Cadence Training Services now offers digital badges for this training course. These badges indicate proficiency in a certain technology or skill and give you a way to validate your expertise to managers and potential employers. You can highlight your expertise by adding these digital badges to your email signature or any social media platform, such as Facebook or LinkedIn. To become Cadence Certified, you can find additional information here.

Related Resources

 Videos

Invoking the MarkNet, Net Tracer command and its options

Net Tracer Features

Video: Net Tracer saving and loading saved trace, neighboring shapes of trace

Net Tracer: Physical Tracing – Step mode

Net Tracer: Physical and Logical Tracing

Video: Net Tracer show preview option, from net and display options, shape count in trace

Video: Net Tracer using a constraint group with different display mode settings and  using the Trace Manager GUI

 RAK

Introduction to Net Tracer

 Product manual

Virtuoso Layout Suite XL: Connectivity Driven Editing User Guide IC23.1

About Knowledge Booster Training Bytes

Knowledge Booster Training Bytes is an online journal that relays information about Cadence Training videos, online courses, and upcoming webinars that are available in the Learning section of the Cadence Learning and Support portal. This blog category brings you direct links to these videos, courses, and other related material on a regular basis.

Sandhya.

On behalf of the Cadence Training team





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Spectre 24.1 Release Now Available

The SPECTRE 24.1 release is now available for download at Cadence Downloads. For information on supported platforms and other release compatibility information, see the README.txt file in the installation hierarchy.(read more)




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Doc Assistant A-Z: Making the Most of the Cadence Cloud-Based Help Viewer Part 3

Welcome back to the Doc Assistant A-Z blog series!

Since the launch of Doc Assistant, we've been gathering feedback and input from our customers regarding their experiences with our latest documentation viewer. My interaction with Ralf was particularly useful and interesting.

Ralf is a design engineer who works on complex schematics and intricate layouts. For each release, he is challenged with the task of verifying the tool and feature changes across multiple releases. He shared with me that he has been using Doc Assistant’s capabilities to help him achieve this.

Ralf explained that he utilizes Doc Assistant to open and compare documents from different releases side-by-side, seamlessly tracking updates across multiple releases and verifying those updates in his Cadence tools. Additionally, in Doc Assistant’s online mode, he compares documents across previous tool versions, ensuring a thorough review of any changes. Finally, he was happy to share with me that Doc Assistant features have helped him significantly reduce the time he spends on identifying such changes.

You, of course, can also achieve such productivity gains using several Doc Assistant features designed to help simplify such tasks!

In previous editions of this blog series, we looked at some key features and benefits of Doc Assistant. If you've missed these editions, I would highly recommend that you read them:

In this third installment, we're diving into some more of Doc Assistant's key capabilities.

Open Multiple Documents

Want to refer to multiple docs at the same time? That’s easy!

Open each doc on a separate tab in Doc Assistant. 

Personalized Content Recommendations

Is it a hassle to navigate through all docs each time? You don’t have to.

You can tailor your Doc Assistant preferences to match your content requirements.

PDF Support

Do you prefer downloading and reading a PDF instead of an HTML?

That’s also supported.

Quick Access to Relevant Search Results

Are you pressed for time, and yet want to run a comprehensive doc search? You’re covered.

In online mode, search runs on all available product documentation, and the results are listed from multiple sources.

Resource Links

Looking for more information about a topic you’ve just read? That’s handy.

Look out for content recommendations!

Share Content

Want to share a useful doc with the rest of your team? That’s easy.

With a single click, Doc Assistant lets you share content with one or more readers.

Submit Feedback

Your feedback is important to us. Use the Submit Feedback feature to share your comments and inputs.

To learn more about how to use the above features, check out the Doc Assistant User Guide.

These are just a few of the productivity gain features in Doc Assistant. We’ll cover more in the next blog in the series.

Want to Know More?

Here's a video about Doc Assistant
Visit the Doc Assistant web page
Read the Doc Assistant FAQ document

If you have any feedback on Doc Assistant or would like to request more information or a demo, please contact docassistant.support@cadence.com.

Subscribe to receive email notifications about our latest Custom IC Design blog posts.

Happy reading!

Priya Sriram, on behalf of the Doc Assistant Team





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10 Layer PCB project won't generate Gerber's completely for middle layers

Hello Fellow PCB Designers,

We have a 10 layer PCB design that originated in Pads and was converted over to Allegro 17.4, this is an old design but is manufacturable and works perfectly fine.  When I try to generate a Gerber for the Top or Bottom layers

the Gerber comes out fine.  But Most of the middle layers are Etch's and via's for power and grounds, but the Gerber's come mostly blank, there might be some details, but in the Gerber view everything is displayed correctly.

The design does have many close spacings, I have not changed anything in the constrains manager yet, turned off a lot of the DRC's, but thinking there might be something wrong with the constrains.

  I find that the CSet is set to 2_18, not sure yet what this means, also there are many of these definitions, PCS 3,4,5,ect, are the same as CSet 2_18 any suggestions would be great, we are currently looking into this, have seen

that even small change in constraint manager can cause long processing and even Allegro crashing, this is a large project.

Thanks Much, Thanks, Mike Pollock.




w

How to transfer custom title block from Orcad Capture to PCB Editor

Hi,

So I was trying to update the title block of a schematic that I have. The title block that was on there was out of date . I clicked on place --> title block and was able to find the title block that I need. I also have a .OLB file that contains that title block. Then I created a Netlist with the old BRD file as the input file (To keep it as is but modify changes) but when I do that I still do not see / cannot place the title block that I need. Under Place --> format symbols in Allegro , I do see a title block that is coming from the database (But it's the old one). I don't know what to do at this point and would appreciate any tips. I did make sure that the path to where the library is , is defined in the user preferences. 
I also tried copying the title block under the library folder in capture before creating my Netlist and that did not work either.

Thank you all.




w

Can I align pin numbers in edit part windows in Orcad Capture?

Hello..

I'm updating part in part editor in orcad capture, and I wonder how to align pin numbers using menu or tcl/tk command.

Please, let me know. Thank you.




w

17.4 Design Sync Fails without providing errors

As the title suggests I am unable to perform design sync between OrCAD Capture and Allegro. When I add a layout and try to sync to it I am given ERROR(ORCAP-2426): Cannot run Design Sync because of errors. See session log for error details.

Session Log

[ORPCBFLOW] : Invoking ECO dialog.
INFO(ORNET-1176): Netlisting the design
INFO(ORNET-1178): Design Name:
C:USERSDDOYLEDOCUMENTSCADENCEBOARDSREMOTE POWER DEVICECAPTUREREMOTE_POWER_DEVICE.DSN
Netlist Directory:
c:usersddoyledocumentscadenceoards emote power devicelayoutallegro
Configuration File:
C:CadenceSPB_17.4 ools/capture/allegro.cfg
pstswp.exe - pst - d "C:USERSDDOYLEDOCUMENTSCADENCEBOARDSREMOTE POWER DEVICECAPTUREREMOTE_POWER_DEVICE.DSN"- n "c:usersddoyledocumentscadenceoards emote power devicelayoutallegro" - c "C:CadenceSPB_17.4 ools/capture/allegro.cfg" - v 3 - l 31 - s "" - j "PCB Footprint" - hpath "HPathForCollision"
Spawning... pstswp.exe - pst - d "C:USERSDDOYLEDOCUMENTSCADENCEBOARDSREMOTE POWER DEVICECAPTUREREMOTE_POWER_DEVICE.DSN"- n "c:usersddoyledocumentscadenceoards emote power devicelayoutallegro" - c "C:CadenceSPB_17.4 ools/capture/allegro.cfg" - v 3 - l 31 - s "" - j "PCB Footprint" - hpath "HPathForCollision"
{ Using PSTWRITER 17.4.0 d001Dec-14-2021 at 09:00:49 }

INFO(ORCAP-36080): Scanning netlist files ...

Loading... c:usersddoyledocumentscadenceoards emote power devicelayoutallegropstchip.dat

Loading... c:usersddoyledocumentscadenceoards emote power devicelayoutallegropstchip.dat

Loading... c:usersddoyledocumentscadenceoards emote power devicelayoutallegropstxprt.dat

Loading... c:usersddoyledocumentscadenceoards emote power devicelayoutallegropstxnet.dat
packaging the design view...
Exiting... pstswp.exe - pst - d "C:USERSDDOYLEDOCUMENTSCADENCEBOARDSREMOTE POWER DEVICECAPTUREREMOTE_POWER_DEVICE.DSN"- n "c:usersddoyledocumentscadenceoards emote power devicelayoutallegro" - c "C:CadenceSPB_17.4 ools/capture/allegro.cfg" - v 3 - l 31 - s "" - j "PCB Footprint" - hpath "HPathForCollision"
INFO(ORNET-1179): *** Done ***

This issue started to occur after I changed parts that exist on previously created PCBs. I changed the following leading up to this:

1. Added height in Allegro to many of my components using the Setup->Area->Package Height tool.

2. Changed the reference designator category in OrCAD Capture to TP for several components on board.

Any advice here would be most welcome. Thanks!




w

Allegro 17.4 always reports new files as created in 17.2

Hello. I am using Cadence 17.4 tools. When I open a package symbol (.dra) or board file (.brd) in Allegro that was created in an older version of the tool I get a message like this one (as expected):

"The design created using release 17.2 will be updated for compatibility with the current software..."


If I create a symbol or board file from scratch in the 17.4 tool then open it later, I get the same message. (always referring to version 17.2 which is the previous version I was using here).

So far this has not caused me any problems, but I would like to understand why it is doing this in case I have something setup incorrectly.

I only have version 17.4 installed. I am not exporting to a downrev version when I save (i.e. not using File->Export->Downrev design…) and in User Preferences->Drawing I don’t have anything selected for database_compatibility_mode. What else might I check?

FYI here is the tool version information that I see after selecting Help->About Symbol:

OrCAD PCB Designer Standard 17.4-2019 S012 [10/26/2020] Windows SPB 64-bit Edition


Thanks -Jason




w

How to magnify a board on a film view

I have a small board that is not readable even though the document is 11' x 17'. Is there a way I could expand/magnify the board along with the components on them to make them legible? 
I have created a new film and is displaying the bottom and top side of the board but the board is too small and the components are not legible. Perhaps there is a way to upscale it or expand it?
Please note I have other stuff in the document that I am not showing , notes and other things, and I am trying to make just the boards look bigger in some way.
I do have a PDF image of the same file where the board appears to be MUCH bigger and is fully legible and I am trying to match that.


Thank you all.




w

No windows cascading in OrCAD Capture 17.4

Hello All,

I'm a novice to this forum and probably this subject has been already discussed here.

My company has purchased OrCAD Capture 17.4 tools that have a new GUI if compared to my earlier used OrCAD Capture 9.2. I have been using Capture 9.2 for ~18 years and its GUI is really convenient. The GUI of 17.4 looks to be a modern one with new icons and really has improved features and new capabilities.

However, my main complain about GUI 17.4 is that the schematic windows cannot be cascaded. Although they can be set floating, this is even more annoying because all toolbars remain in the Capture window and when you select a tool, the Capture window pops over already open schematic window and you need a lot of useless extra clicks to return back to the currently edited schematic page. I always used cascading of schematic windows before because my complex designs includes many pages, not speaking about the library windows that are typically open simulatneously. My view is that the lack of CASCADING in Capture GUI 17.4 is critical and unacceptable for complex projects, and I would very highly appreciate if the Cadence guys will return back the CASCADING capability for schematic pages. In case this will be done, this will make the GUI really great and comfortable to use.

Does anybody have opinion on this issue?

Many thanks,

Pavel




w

Netlisting error when doing parametric sweep on transient simulation

Dear all,

I defined two design variables in ADE Assembler, say V1 and V2, that define the voltage 1 and voltage 2 of a "vpulse" voltage source in my schematic.

Then, I define V1 = 1.0, and V2 = 2.0, run a transient simulation, and everything is as expexcted. The source provides pulses between 1.0 V and 2.0 V.

Next, I set V1 = 1.0:0.5:1.5, thereby creating a parametric sweep with 1.0 V and 1.5 V for V1. I keep V2 at 2.0 V. Then the simulation fails, and all I get is "netl err" in my Output Expressions and an error message that the results directory does not exist and nothing can be plotted: This is reasonable, as the results directory is deleted on starting a new simulation, and as there is no simulation result, none of my output expressions can be plotted.

WARNING (OCN-6040): The specified directory does not exist, or the directory does not contain valid PSF results.
        Ensure that the path to the directory is correct and the directory has a logFile and PSF result files.
WARNING (ADE-1065): No simulation results are available.
ERROR (WIA-1175): Cannot plot waveform signals because no waveform data is available for plotting.
One of the possible reasons can be that 'Save' check box for these signals are not selected in the Outputs Setup pane. Ensure that these check boxes are selected before you run the simulation.

Normally, this kind of para,metric sweep is not a problem, I have done this many times before. There must be something special in THIS PARTICULAR test bench or simulator setup. The trouble is, I don't get any useful error messages.

Does anyone know what might be the problem here OR where to find useful information to investigate further (log files stored somewhere)? Thank you!

Regards,

Volker

P.S. Using Corners instead does not help either. Running it through all values by hand works, though.




w

A problem with setup when Monte Carlo simulation starts

Hi, 

When I try to run Monte Carlo it gives me a 3 items message for possible failure:

1. It says the machine selected in the current job setup policy isnot reachable

2. The Cadence hierarchy is not detected, not installed properly. or

3. Job start script (with a path and a name like swiftNetlistService#) is not found on the remote machines.

Any recommendation on how to fix this?




w

New CDF creation and callback

I need to add a new CDF parameter called "mag" to symbols in a given library using skill script in which the symbol size can be controlled and call back it each time this library is used so that all the symbols are updated.




w

Config sweep View in Tests

Hi all,

I have a question regarding how to sweep the config view without using a global variable. I’d like to set a different config view for each test, and I'm trying to avoid using corners or plan.

Any suggestions on how to achieve this?

Thanks in advance for your help!

Best,
MooH




w

How can I place stacked vias with the size exact same cut width without metals around?

How can I place stacked vias with the size exact same cut width without metals around?
As the red part only in the image below?




w

Change code in veriloga view from external program

For reasons too complicated to go into here, I need to generate the code for a veriloga view from a outside the normal Verilog-A editor. I would start with an "empty" veriloga view generated from the symbol in the normal way so I get the port order correct, then use external code to provide "guts" of the veriloga view by overwriting the generated code.

My understanding is that and code changes made external to the normal flow do not get picked up by Cadence - the Verilog-A code gets read at design time, not at netlist time. Would simply forcing a check and save of the veriloga view after the code is modified fix that problem? Or is there an easier way to incorporate externally generated Verilog-A code?




w

How to use PSpice library in Virtuoso/Spectre?

I want to use PSpice model (download from TI) in Virtuoso , but it can not work. Please help me to check the error message, Thanks

ADE-> Setup-> simulation files->Pspice  Files  /TPS628502-Q1_TRANS.LIB

Parse error before token ']' in expression '[[STEADY_STATE]*0.6]'. If '[[STEADY_STATE]*0.6]'  is a spice expression, quotes are required for the expression.

ERROR(SFE-46): An instance of 'TPS628502-Q1_TRANS'  can have at most 8 terminals (but has 9).

*****************************************************************************
.SUBCKT TPS628502-Q1_TRANS COMP_FSET EN FB GND PG SW SYNC_MODE VIN
+ PARAMS: STEADY_STATE=0
V_U9_V45 U9_N16725824 0 5
E_U9_ABM22 U9_N16725392 0 VALUE { V(FREQ)*1e-12 }
X_U9_U161 U9_N16849713 U9_N16846056 one_shot PARAMS: T=20




w

Verilog-A: Can I ignore WARNING (VACOMP-1047)

I need to include Verilog-A files which live outside the Cadence ecosystem (i.e., they are not in veriloga views but rather are just text files) into a veriloga view. These external modules are not compatible with OA (parametized port widths) so I can't put them into cellviews and hook them together using schematics.

Example: I have a cellview "test" which has a symbol and veriloga view. I have three "externaI" modules mod1 (inside an external file mod1.va),  mod2 (inside an external file mod2.va),  and mod3 (inside an external file mod3.va). I instantiate one instance of each module in "module test". The three modules have some parametized ports which are interconnected by parameterized signals p1 and p2. These two signals are strictly local to the module.

At the bottom of the module I use "`include mod1.va", "`mod2.va", etc.

When I check and save test->veriloga it checks all the included modules as well as the "test" module. However, I get a warning:

Warning from spectre during AHDL compile.
WARNING (VACOMP-1047): The Verilog-A file contains more than one module
definition. ADE can process only one module per Verilog-A file. Put
only one module in each Verilog-A file so that ADE can identify pin
names, directions, and hierarchy within each separate module.

Is this just a SUGGESTION that I can safely ignore, or are my included modules going to be ignored?




w

Xcelium/Simvision/xrun running very slow (waiting for SimVision/Verisium Debug to connect...)

Hello,


I would like to use the simulation software xrun/simvision that comes with XCELIUM. We are currently using classroom licenses and want to disable all ip addresses on the student pcs except the license server ip. We want to make sure that students cannot copy confidential data from the Cadence tools.


Problem:

When I launch the xrun simulation while all ip addresses are blocked, it starts but the performance is very slow. The GUI starts after 5 minutes and the simulation is ready after 10 minutes. The interesting thing is that when I enable all blocked ip addresses, everything works at a reasonable speed.

Terminal Output (execution without internet connection):

xrun -gui design.vhd

waiting for SimVision/Verisium Debug to connect...


Is there a way to run the simulation tools without an Internet connection? Or can you give me the ip addresses that are used by the simulation tools so that I can enable only those specific ips?


Regards,

Max




w

Transient Simulation waveform abnormal

Hello Everybody

Recently, I want to design a high output Power Amplifier at 2.4GHz using TSMC 1P6M CMOS Bulk Process. I use its nmos_rf_25_6t transistor model to determine the approximate mosfet size

I use the most common Common-Source Differential Amplifier topology with neutralizing capacitor to improve its stability and power gain performance

Because I want to output large power, the size of mosfet is very large, the gate width is about 2mm, when I perform harmonic balance analysis, everything is alright, the OP1dB is about 28dBm (0.63Watt)

But When I perform Transient simulation, the magnitude of voltage and current waveform at the saturation point is too small, for voltgae, Vpeaking is about 50mV, for current, Ipeaking is about 5mA

I assume some reasons: the bsim4 model is not complete/ the virtuoso version is wrong (My virtuoso version is IC6.1.7-64b.500.21)/the spectre version is wrong (spectre version is 15.1.0 32bit)/the MMSIM version is wrong/Transient Simulation setting is wrong (the algorithm is select gear2only, but when I select other, like: trap, the results have no difference), the maxstep I set 5ps, minstep I set 2ps to improve simulation speed, I think this step is much smaller than the fundamental period (1/2.4e9≈416ps)

I have no idea how to solve this problem, please help me! Thank you very very much!




w

How to get maximum value of s11 Trace

Hello

i did a sp-Analysis and now i want to extract the maximum value of the s11 trace and the corresponding frequency.

I already tried ymax() in the calculator but i am suspecting it only works on transient Signals.




w

error when generating snp files from a variable

Hello everyone, 
I have a testbench for generating s2p files from a SP simulation that was working until few months ago. Today I have reopened (w/o making changes that I am aware of) and I get the error as shown below:

first I show the testbench settings:

notice how the s2p generation is disabled: the field "file" is left blank

in the corner I defined some parameters, "filename" is the word that is suppose to generate the name for the s2p. 

where the two variables are defined as follows

And now the output log:

spectre.out file gives the following error:


When clicking on the error message at "9", the input.scs file opens up and the line 9 gets highlighted in green



now, so far I understood that the problem seem to be related tom the "pathcds" variable, but I really don't understand what the error message here means, since I don't see any error in the input.scs file

by the way - if for instance I define the variable "filename" as shown below, then I get no errors:


thanks
Tommaso




w

Colorcoding for low cpk in Yield-View in Assembler

Hi,

I'm searching for a way to get a quick overview of too low cpk-values after a montecarlo sim. The non-MC results have the spec and thus the easy/understandable red/green/(yellow) colorcoding, but for MC sims I don't get a highlight for high variations inside the limits.

Is this possible (besides copying each expression into avg()+3*std()) and ..-..)?

It would be really handy to scan through finished sims...

(My final application is then to export the table for my reports and documentation...)

Regards,

leo




w

Force virtuoso (Layout XL) to NOT create warning markers in design

Hi

I have a rather strange question - is there a way to tell layout XL to NOT place the error/warning markers on a design when I open a cell?  I do a lot of my layout by using arrays from placed instances and create mosaics that completely ignore the metadata that Layout XL uses with its bindings with schematic (and instances get deleted etc. but I do like using it to generate all my pins etc.) and it's just really annoying when I open a design that I know is LVS clean and since the connectivity metadata is all screwed up (because I did not use it to actually complete the layout) I have a design that's just blinking at me at every gate, source and drain.  I typically delete them at the high level heirarchically but the second I go in and modify something and come back up it places all of them again.  I know that if I flatten all the p cells it goes away but sometimes it's nice to have that piece of metadata but that's about it.  Is there a way to "break" the features of XL like this?  I realize what a weird question this is but it's becoming more of an issue since we moved to IC 23 from IC 6 where there is no longer a layout L that I can use free from these annoyances that can't use any of the connectivity metadata.

Thanks

Chris




w

How to Set Up a Config View to Easily Switch Between Schematic and Calibre of DUT for Multiple Testbenches?

Hello everyone,

I hope you're all doing well. I’ve set up two testbenches (TB1 and TB2) for my Design Under Test (DUT) using Cadence IC6.1.8-64b.500.21 tools, as shown in the attached figure. The DUT has multiple views available: schematic, Calibre, Maestro, and Symbol, and each testbench uses the same DUT in different scenarios. Currently, I have to manually switch between these views, but I would like to streamline this process.

My goal is to use a single config view that allows me to switch between the schematic and the extracted (Calibre) views. Ideally, I would like to have a configuration file where making changes once would update both testbenches (TB1 and TB2) automatically. In other words, when I modify one config, both testbenches should reflect this update for a single simulation run.

I would really appreciate it if you could guide me on the following:

  1. How to create a config view for my DUT that can be used to easily switch between the schematic and extracted views, impacting both TB1 and TB2.
  2. Where to specify view priorities or other settings to control which view is used during simulation.
  3. Best practices for using a config file in this scenario, so that it ensures consistency across multiple testbenches.

Please refer to the attached figure to get a better understanding of the setup I’m using, where both TB1 and TB2 include the same DUT with multiple available views.

Thank you so much for your time and assistance!




w

Tagging uvm_errors in waveform file for post-processing

Hi,

Do anyone know if it's possible in simvision waveform viewer to see a timestamp of where uvm_errors/$errors occurred in a simulation via post-processing? 

Cheers,

Antonio




w

Using Xcelium, xrun -nogui option, where are the simulation results

I'm completely new to Cadence. I've been able to run a very simple simulation with the -gui option. Simvision opens, I add the variables to the waveform viewer, and press run. All is good.

I don't understand the flow when using the -nogui option. It appears that the simulation runs and returns control to the OS. When I launch Simvision, is there a database or file that I can open to display the already-simulated data?

My command is of the form:

xrun -gui -64bit -sv -access +rwc -top tb_top.sv <src files>




w

UVM debugging: How to save and load signals during an interactive session in Simvision

Hello,

I am aware of command script .svcf file that saves signals and loads them in while opening Simvision.

I am wondering, if there is a way for saving signals while we are in an interactive session and loading them next time when we open Simvision interactively.

Any ideas on how to do this?

Thank you in advance.

Swetha. C




w

vManager crashes when analyzing multiple sessions simultaneously with a fatal error detected by the Java Runtime Environment

When analyzing multiple sessions simultaneously Verisium Manager crashed and reported below error messages:

# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0x00007efc52861b74, pid=14182, tid=18380
#
# JRE version: OpenJDK Runtime Environment Temurin-17.0.3+7 (17.0.3+7) (build 17.0.3+7)
# Java VM: OpenJDK 64-Bit Server VM Temurin-17.0.3+7 (17.0.3+7, mixed mode, sharing, tiered, compressed oops, compressed class ptrs, g1 gc, linux-amd64)
# Problematic frame:
# C  [libucis.so+0x238b74]

......

For more details please refer to the attached log file "hs_err_pid21143.log".

Two approaches were tried to solve this problem but neither has worked.
Method.1:

Setting larger heap size of Java process by "-memlimit" options.For example "vmanager -memlimit 8G".

Method.2:

Enlarging stack memory size limit of the Coverage engine by setting "IMC_NATIVE_STACKSIZE" environment variable to a larger value. For example "setenv IMC_NATIVE_STACKSIZE 1024000"

According to "hs_err_pid*.log" it is almost certain that the memory overflow triggered Java's CrashOnOutOfMemoryError and caused Verisium Manager to crash. There are some arguments about memory management of Java like "Xms, Xmx, ThreadStackSize, Xss5048k etc" and maybe this problem can be fixed by setting these arguments during analysis. However, how exactly does Verisium Manager specify these arguments during analysis? I tried to set them by the form of setting environment variables before analysis but it didn't work in analysis and their values didn't change.

Is there something wrong with my operation or is there a better solution?

Thank you very much.




w

explain/correct my understanding between average/covered in imc metrics

I'm working on the code coverage. Doing a metrics analysis by default we see overall average grade and overall covered. But when i do a block analysis on an instance i see overall covered grade, code covered grade, block covered grade, statement covered grade, expression covered grade, toggle covered grade.

As I dont know the difference I started to read the IMC user guide and came to know there are 3 things we come across while doing a code coverage local, covered, average

From my understanding

local - child instances metrics doesnt reach the parent level. For example, we have an instance Q and its sub instances like Q.a, Q.b. Block Local grade of Q can be 100% even when its instances Q.a and Q.b a block local grades isnt at 100%.

In the attached image there is formula 

The key difference between average and covered is the weights.

Average : Mathematically taking the above scenario where Q.a, and Q.b has 10 blocks each. Q.a has covered 8 blocks and q.b has covered 2 blocks. Now if we take the normal average it should be total covered/ totatl number = 8+2/10+10 yielding 50%. But when we add weights saying Q.a is 70% and Q.b is 30% the new number would be (8*0.7+2*0.3) / (10*0.7+10*0.3) resulting 62%. Because of the weights we see 12% bump.

Covered: there is no role of weights.

Among these 3 metrics i've changed my default view to this in the image to get more realistic picture when i do analyze metrics. Do you guys agree with the approach?




w

How do I create a basic connectivity csv?

First time user of JasperGold. Chip level verif. I want to prove that an arbiter and a buffer are connected. I want to use the connectivity app to do that.

I see from the user guide, that I should provide a connectivity map, but i have no idea how to construct one.
The training videos said use this command: check_conn -generate_template jasper_template.xlsm -xlsm
But that did nothing, or at least it did not produce a file that i could find


[<embedded>] % check_conn -generate_template jasper_template.xlsm -xlsm
ERROR (ESW104): Invalid command formation.
Problem occurs with "-generate_template -xlsm".

And even if it did, I don't even know what's in the file, and whether it contains the two ips I'm trying to check.

I'm hoping someone can give me a bit of a boost here with some knowledge.




w

[Xcelium][xrun] Simulate with multiple builds

I want to do a 2-step build->simulate as follow:

1. Make multiple builds using xrun -elaborate [other options]. The purpose is to create multiple builds with different compile-time macros (+define+MACROA +define+MACROB=ABC). Each build is located in a different directory.

2. Run simulation with xrun -r. This is where I need help. How do I specify which build to simulate? Also, I need the simulation directory (with log files, …) to be different than the build directory.

Has anyone been able to achieve this or similar solutions?




w

"How to disable toggle coverage of unused logic"

I'm currently work in coverage analysis. In my design certain register bits remain unused, which could potentially lower toggle coverage. Specifically, I'd like to know how to disable coverage for specific unused register bits within a 32-bit register. For instance, I want to deactivate coverage for bit 17 and bit 20 in a 32-bit register to optimize toggle coverage. Could you please provide guidance on how to accomplish this?




w

Is it possible to automatically exclude registers or wires that are not used from toggle coverage?

Hello,

I have a question about toggle coverage.

In my case, there are many unused registers or wires that are affecting the toggle coverage score negatively.

Is it possible to automatically exclude registers or wires that are not used from toggle coverage?

My RTL code is as follows, Is it possible to automatically disable tb.top1.b and tb.top1.c without using an exclude file?

module top1;

  reg a;

  reg b;

  reg [31:0] c;

  initial

  begin

  #1 a=1'b0;

  #1 a=1'b1;

  #1 a=1'b0;

  end

endmodule

module tb;

  top1 top1();

endmodule




w

Auto-Coloring Waves in Simvision?

Hello,

First, I had something working that broke in the past few versions that I've been meaning to get working again. There was some setting I recall in the GUI that allowed me to have inputs be placed in the waveform viewer with yellow traces, and output signals with orange traces to match the name colors. How can I set this to happen in the .simvisionrc file?

Second, I would like to add something to my .simvisionrc file to go through foreach signal and depending on key locations based on the signal's Path.Name (mainly the model and design areas) such that if the path contains "mon", then to auto-set the trace and name colors to something such as cyan. I'd like to have loops for various key areas of the design to color-code the signals.

Third, I am interested if there is a possibility of coloring names/traces foregound colors to based on which position they are in the waveform viewer to make banding, ideally such that every three (or whatever) are one color (or a color mutation, adding some gray to signals colorized by the auto-coloring mentioned already, etc) that allows for the signal names/traces to be colorized along with the built-in optional black/gray background banding.

Thanks in advance




w

c interface with specman

Hi,

 I need to call a  c function form specman . I had followed the below steps.


File vb_pattern.e
---------------------------------

 
struct vb_pattern_s
{
  %data_in_ch0 : uint (bits : 4);   // data on channel 0
  %data_in_ch1 : uint (bits : 4);   // data on channed 1
  %data_in_ch2 : uint (bits : 4);   // data on channel 2
  %mode : uint (bits : 1);          // mode 
  %enable : uint (bits : 1);        // enable

};

C export vb_pattern_s;

------

file  x_output_bfm.e
--------------------------------------------

check_patterns()@clk_e is
{

  ...
 exp_viterbi_op();

}

routine exp_viterbi_op() is C routine viterbi_c_func;

---- EOF------

X.c
#include "vb_pattern.h"

void viterbi_c_func ()
{
 SN_TYPE(vb_pattern_s) vb_packet;
 SN_TYPE(mode)   mode;
 vb_packet = SN_SYS->ops
 mode = vb_packet->mode;
 printf(" Printing from C environment MODE = %h ", mode);

}


------------------- EOF----

x_top.e
------------
import  tb/vb_pattern.e;
import  tb/x_input_bfm.e;
import  tb/x_output_bfm.e;
import  tb/x_cover_dut.e;
import  tb/x_env.e;




I  did the following comand


>> sn_compile.sh -h_only x_top.e -o vb_pattern.h
>> gcc -c viterbi.c -o viterbi.o

I am getting the following error


viterbi.c: In function `viterbi_c_func':
viterbi.c:6: error: `t__mode' undeclared (first use in this function)
viterbi.c:6: error: (Each undeclared identifier is reported only once
viterbi.c:6: error: for each function it appears in.)
viterbi.c:6: error: syntax error before "mode"
viterbi.c:7: error: `mode' undeclared (first use in this function)


Please help me resolve this.

Kesav



  








 


Originally posted in cdnusers.org by kesava




w

Macro for multiple-value when definitions

The two macros below introduce new syntax for adding definitions to more than one 'when' determinant value at the same time. The first macro overloads 'extend' keyword and the second is the equivalent for 'when' keyword.

A use example:

extend [HUGE, BIG] packet {
    // definitions that pertain to these subtypes
};


The above code would be expanded in the following (naive) way:

extend HUGE packet {
    // definitions that pertain to these subtypes
};
extend BIG packet {
    // definitions that pertain to these subtypes
};



The macros code:

define 'statement>
       "extend ['name>,...] 'name> ({;...})" as computed {
    for each in 'names> do {
        result = appendf("%sextend %s %s %s;",result,it,'name>,);
    };
    result = appendf("{%s}",result); // required only for versions 6.1.1 or earlier
};

define 'struct_member>
       "when ['name>,...] 'name> ({;...})" as computed {
    for each in 'names> do {
        result = appendf("%swhen %s %s %s;",result,it,'name>,);
    };
    result = appendf("{%s}",result); // required only for versions 6.1.1 or earlier
};


Originally posted in cdnusers.org by matanvax




w

ce_tools directory no longer shipped with Specman

Hello All,

starting with version 8.1 the contents of the ce_tools directory will no longer
be shipped with Specman. The directory contains some unsupported AE/R&D
ware and has not been updated for several releases (i.e. most of those old
packages don't work with the latest release).
 
Attached is the contents of this directory. Please read the README before
using any of the packages.


Regards,
-hannes


Originally posted in cdnusers.org by hannes




w

Welcome! Please use this forum to upload your code

Please include a brief summary of how to use it.