In the former blog about Python and Specman: Specman: Python Is here!, we described the technical information around Specman-Python integration. Since Python provides so many easy to use existing libraries in various fields, it is very tempting to leverage these cool Python apps.

Coverage has always been the center of the verification methodology, however in the last few years it gets even more focus as people develop advanced utilities, usually using Machine Learning aids. Anyhow, any attempt to leverage your coverage usually starts with some analysis of the behavior and trends of some typical tests. Visualizing the data makes it easier to understand, analyze, and communicate. Fortunately, Python has many Visualization libraries.

In this blog, we show an example of how you can use the plotting Python library (matplotlib) to easily display coverage information during a run. In this blog, we use the Specman Coverage API to extract coverage data, and a Python module to display coverage grades interactively during a single run and the way to connect both.

Before we look at the example, if you have read the former blog about Specman and Python and were concerned about the fact that python3 is not supported, we are glad to update that in Specman 19.09, Python3 is now supported (in addition to Python2).

The Testcase
Let’s say I have a stable verification environment and I want to make it more efficient. For example: I want to check whether I can make the tests shorter while hardly harming the coverage. I am not sure exactly how to attack this task, so a good place to start is to visually analyze the behavior of the coverage on some typical test I chose. The first thing we need to do is to extract the coverage information of the interesting entities. This can be done using the old Coverage API. 

Coverage API
Coverage API is a simple interface to extract coverage information at a certain point. It is implemented through a predefined struct type named user_cover_struct. To use it, you need to do the following:

1. Define a child of user_cover_structusing like inheritance (my_cover_struct below).
2. Extend its relevant methods (in our example we extend only the end_group() method) and access the relevant members (you can read about the other available methods and members in cdnshelp).
3. Create an instance of the user_cover_structchild and call the predefined scan_cover() method whenever you want to query the data (even in every cycle). Calling this method will result in calling the methods you extended in step 2.  

 The code example below demonstrates these three steps. We chose to extend the end_group() method and we keep the group grade in some local variable. Note that we divide it by 100,000,000 to get a number between 0 to 1 since the grade in this API is an integer from 0 to 100,000,000. 

Pass the Data to a Python Module
After we have extracted the group grade, we need to pass the grade along with the cycle and the coverage group name (assuming there are a few) to a Python module. We will take a look at the Python module itself later. For now, we will first take a look at how to pass the information from the e code to Python. Note that in addition to passing the grade at certain points (addVal method), we need an initialization method (init_plot) with the number of cycles, so that the X axis can be drawn at the beginning, and end_plot() to mark interesting points on the plot at the end. But to begin with, let’s have empty methods on the Python side and make sure we can just call them from the e code.

 # plot_i.py
def init_plot(numCycles):
    print (numCycles)
def addVal(groupName,cycle,grade):
    print (groupName,cycle,grade)
def end_plot():
    print ("end_plot") 

And add the calls from e code:

 Before running this, note that you need to ensure that Specman finds the Python include and lib directories, and Python finds our Python module. To do this, you need to define a few environment variables: SPECMAN_PYTHON_INCLUDE_DIR, SPECMAN_PYTHON_LIB_DIR, and PYTHONPATH. 

 The Python Module to Draw the Plot
After we extracted the coverage information and ensured that we can pass it to a Python module, we need to display this data in the Python module. There are many code examples out there for drawing a graph with Python, especially with matplotlib. You can either accumulate the data and draw a graph at the end of the run or draw a graph interactively during the run itself- which is very useful especially for long runs.

Below is a code that draws the coverage grade of multiple groups interactively during the run and at the end of the run it prints circles around the maximum point and adds some text to it. I am new to Python so there might be better or simpler ways to do so, but it does the work. The cool thing is that there are so many examples to rely on that you can produce this kind of code very fast.

 In the example we used, we had two interesting entities: packet and state_machine, thus we had two equivalent coverage groups. When running our example connecting to the Python module, we get the following graph which is displayed interactively during the run.

When analyzing this specific example, we can see two things. First, packet gets to a high coverage quite fast and significant part of the run does not contribute to its coverage. On the other hand, something interesting happens relating to state_machine around cycle 700 which suddenly boosts its coverage. The next step would be to try to dump graphic information relating to other entities and see if something noticeable happens around cycle 700.

To run a complete example, you can download the files from: https://github.com/okirsh/Specman-Python/

Do you feel like analyzing the coverage behavior in your environment? We will be happy to hear about your outcomes and other usages of the Python interface.

Orit Kirshenberg
Specman team

We're happy to have guest blogger Thorsten Dworzak, Principal Consultant at Verilab GmbH, describe how he added Specman/e syntax to Sublime Text 3:

According to the 2018 StackOverflow Developer Survey, the popularity of development environments (IDEs, Text Editors) among software developers shows the following ranking:

1. Visual Studio Code 34.9%
2. Visual Studio 34.3%
3. Notepad++ 34.2%
4. Sublime Text 28.9%
5. Vim 25.8%
6. IntelliJ 24.9%
7. Android Studio 19.3%
8. (DVT) Eclipse 18.9%
9. …

15. Emacs 4.1%

Of these, only Vim, (DVT) Eclipse, and Emacs support editing in e-language (at least, last time I checked). Kate, which comes with KDE and also has a Specman mode, is not on this list.

I started using Sublime Text 3 some time ago. It offers packages that support a number of programming languages.

Though there is an e-language syntax available from Tsvi Mostovicz, it is unfinished work, and there are many syntactic constructs are missing. So, I created a fork of his project and finished it (it will eventually be merged back here).

It is a never-ending task because my code base for testing is limited and e is still undergoing development. The project is available through ST3's Package Control and you can contribute to it via Github.

I am eagerly waiting for your pull requests and/or comments and contributions!

With ECAD-MCAD Library Creator, you can easily create footprints for your parts using thousands of ready-to-use templates that are provided with the tool.(read more)

All PCB designers know the importance of proper power delivery for successful board design. Integrated circuits need the power to turn on, and ICs with marginal power delivery will not operate reliably. Since power planes can...(read more)

Imagine you are on a vacation with your family, and suddenly, your phone starts buzzing. You pick it up and what are you looking at is a bunch of pending, unanswered e-mails. You start recollecting the checklist you had made before taking off only to realize that you haven’t put on the automatic replies! (read more)

In my previous blog, I talked about creating a footprint using an existing template in Allegro ECAD-MCAD Library Creator and explained how easily you can access an existing template and create a package from it by just clicking a button. In this blog...(read more)

What is a Power Distribution Network (PDN) after all but resistance, inductance, and capacitance in the PCB and components? And, of course, it is there to deliver the right current and voltage to each component on your PCB. But is that all? Are there oth...(read more)

Have you ever manufactured a printed circuit board (PCB) without analyzing all the routed signal traces? Most designers will say “yes, all the time.” Trace widths and spacing are set by constraints, and many designers simply don’t h...(read more)

So, what if you can figure out all that can go wrong when your product is being assembled early on? Not guess but know and correct at an early stage – not wait for the fabricator or manufacturer to send you a long report of what needs to change. That’s why Design for Assembly (DFA) rules(read more)

The IEEE has announced the publication of the new 1801-2013 standard, also known as UPF 2.1, and immediate availability for free download through the IEEE 1801-2013 Get Program. Even though the standard is new to the whole world, for the people of the IEEE working group this standard is finally done and is in the past now.

There is a Chinese saying "好事多磨" which means "good things take time to happen." I forgot the exact time when I first joined the working group for the new standard -- about two and half years ago -- but I do remember long hours of meetings and many "lively" debates and discussions. Since the "hard time" has passed us, I would like to share some fun facts about the working group and the standard.

• The 1801 working group is the largest entity based ballot group in IEEE-SA history.
• The new standard was initially planned for 2012, but was delayed purely due to the large amount of work required.
• At one point, the group was debating on whether the new standard should be called UPF 2.1 or 3.0. It may sound weird now but we spent quite some time discussing this. Eventually we settled on 2.1 as it was the original plan.
• The 1801-2013 document has 358 pages which is 53% thicker than previous version (the sheer amount of changes in the new standard indicate that this is more than just a normal incremental update of the previous version as suggested by naming it 2.1)
• Around 300 real issues were reported over the previous version and a majority of them were fixed in the new release.
• This is the first release with constructs and semantics coming from Common Power Format (CPF), a sign of convergence of the two industry leading power formats.
• There are about 100 working group meetings in my Outlook calendar since 2011, with meeting times ranging from 2 hours to 8 hours.
• We extensively used Google Drive (which was called Google Docs when the working group started), a great tool for productivity. I cannot imagine how any standard could have been done before Google existed!

Personally, I had an enjoyable journey, especially from having the privilege to work with many industry experts who are all passionate about low power. I do have one more thing to share though. My older daughter went from middle school to high school during the period of the development of the new standard. Since most of the meetings took place in the early morning California time, she had to endure the pain of listening to all these discussions on power domain, power switches, etc. on her way to school.

I asked her if she learned anything. She told me that other than being able to recognize the voices of Erich, John and Joe on the line, she also learned that she would never want to become an electrical or computer engineer! She was so happy that the meetings stopped a couple of months ago. But what I did not tell her is that the meetings will resume after DAC! Well, I am sure this will be a big motivation for her to get her own driving license in the summer.

If you want to get some quick technical insights into the new standard, check out my recent EE Times article IEEE 1801-2013: A bold step towards power format convergence.

Qi Wang

Hello, i have a realy mistick thing going with copying libraries in cadence virtuoso,

When i copy straight forwart the whole library it gives me a warning that accsess was denied,but when i go into the library and copy it as a single file, then it goes fine.

another problem is it doesnt show in the massage console  ALL the files which could not be copied.(which is the much bigger problem,becuase i would have to pass threw all the subdirectories to verify if all files are there)

Is there a way to see which files wasnt able to be copied?

Thanks. 

Hello,

Would anyone know how to setup a PSS or QPSS simulation with 25% dutycycle clock sources or if such a thing is possible with QPSS.

Fig1 (below) is a snapshot of the circuit I am trying to characterize. This has 4 clock ports each with 25%duty cycle in the ON state. Fig2 below shows two of these clocks.

Each path in the circuit consists of two switches with a low pass RC sandwiched in between. The Input is a 50Ohm port sine wave and the output is a 1K resistor. The output nets of all paths are connected together.

I am trying to determine the swept frequency response from input to output (voltage) when the input is from 500Mhz to  510MHz. The Period (T=1/Fp) of each of the pulses is such that Fp=500MHz. The first pulse source has a delay=0, second has delay=T/4, third delay=2T/4, etc...

I am currently getting it working and seeing the correct result (bandpass response) with Transient but the problem is doing a dft at 500MHz with 10KHz spacings needs at least 100us and takes up a lot of time and disk space.

Many Thanks,
Chris.

Fig1

Fig2

Hello, I have a problem with a certain type of transistor,my hyrarchy has a lot components an sub components and visually inspecting them is very hard.

is there a way like in other cadence layout viewer tools , to enter the name of the component or a NET somewhere and it will focus on it visualy or give the hyrarchy path to it?

Thanks.

hi everyone, 

i'm trying to create a netlist for aging simulation. i would like to simulate how power, Gain and PAE (efficiency) are inlfuenced after 3 hours

i would be grateful if someone can correct my syntax in the netlist since i'm trying to make a sweep HB  simulation where the input power is the parameter.

i did it without any error for the sp (S parameters)  simulation.

you can see the images for both sp and hb simulation netlists. (from left to right: sp aging netlist; hb aging netlist)

i will be grateful if someone can provide me some syntax advices.

thanks,

best regards

hello there, i'm a student studying allegro PCB designer.

There are some commands that i can do with GUI, but i want to know what kind of commands i used so that i can route with commands only(ex) skill).

Is there any file that i can see what kind of commands i used something like log files or command history?

thank you for reading this long boring question.

Hi experts,

I have a problem with my design as below

ERROR: in SHAPE (-2.3622 2.3622)

  class = ETCH

  subclass = TOP 

  Part of Symbol Def SHAPE_4725X4725.

      Which is part of a padstack as a SHAPE symbol.

  ERROR(SPMHDB-187): SHAPE boundary may not cross itself.

   Error cannot be fixed.

       Object has first point location at (-2.3622 2.3622).

Can you tell me how to solve my problem?

Thanks a lot.

I would like to generate the comparison report of database footprint with library footprint if any mismatch available.

Is there a way to take if it possible means can anyone please guide me or share me the skill code please.

Thanks,

Pradeep

Currently I tried this:

axlDBCreateShape(recPolyPlanes t "BOUNDARY/L02" netName sym1)

I get a atom error on car(sym1)

I can do this "static" using ETCH/L02 with out an issue, but I am trying to avoid doing an axlShapeChangeDynamicType().

Thanks,

Jerry

Hello, i am a student who is studying Allegro tool with SKILL.

I have a question about SKILL axlSegDelayAndZ0. The reference says this function "returns the delay and impedance of a cline segment."

I want to know how many components does this tool consider when calculating timing delay from the length. 

How steep is input signal's rise transition? Is rise transition shape isosceles trapezoid or differential increasing shape?

Also, if it is a multi fan-out, the rise transition time will be different net by net. How can this tool can calculate in this case?

I want to hear answers about these questions.

Thank you for reading this long boring questions, and i will be waiting for answers.

Hi 

I'm trying to find the location of the assembly line in the design automatically without using "Show Element". And also I want to find the end points of that line. The line exists in "Package Geometry/Assembly_Top" Layer. So is there any code snippet to find the location of assembly line?

This is the 15th installment of The Rationalist, my column for the Times of India.

It’s election season, and promises are raining down on voters like rose petals on naïve newlyweds. Earlier this week, the Congress party announced a minimum income guarantee for the poor. This Friday, the Modi government released a budget full of sops. As the days go by, the promises will get bolder, and you might feel important that so much attention is being given to you. Well, the joke is on you.

Every election, HL Mencken once said, is “an advance auction sale of stolen goods.” A bunch of competing mafias fight to rule over you for the next five years. You decide who wins, on the basis of who can bribe you better with your own money. This is an absurd situation, which I tried to express in a limerick I wrote for this page a couple of years ago:

POLITICS: A neta who loves currency notes/ Told me what his line of work denotes./ ‘It is kind of funny./ We steal people’s money/And use some of it to buy their votes.’

We’re the dupes here, and we pay far more to keep this circus going than this circus costs. It would be okay if the parties, once they came to power, provided good governance. But voters have given up on that, and now only want patronage and handouts. That leads to one of the biggest problems in Indian politics: We are stuck in an equilibrium where all good politics is bad economics, and vice versa.

For example, the minimum guarantee for the poor is good politics, because the optics are great. It’s basically Garibi Hatao: that slogan made Indira Gandhi a political juggernaut in the 1970s, at the same time that she unleashed a series of economic policies that kept millions of people in garibi for decades longer than they should have been.

This time, the Congress has released no details, and keeping it vague makes sense because I find it hard to see how it can make economic sense. Depending on how they define ‘poor’, how much income they offer and what the cost is, the plan will either be ineffective or unworkable.

The Modi government’s interim budget announced a handout for poor farmers that seemed rather pointless. Given our agricultural distress, offering a poor farmer 500 bucks a month seems almost like mockery.

Such condescending handouts solve nothing. The poor want jobs and opportunities. Those come with growth, which requires structural reforms. Structural reforms don’t sound sexy as election promises. Handouts do.

A classic example is farm loan waivers. We have reached a stage in our politics where every party has to promise them to assuage farmers, who are a strong vote bank everywhere. You can’t blame farmers for wanting them – they are a necessary anaesthetic. But no government has yet made a serious attempt at tackling the root causes of our agricultural crisis.

Why is it that Good Politics in India is always Bad Economics? Let me put forth some possible reasons. One, voters tend to think in zero-sum ways, as if the pie is fixed, and the only way to bring people out of poverty is to redistribute. The truth is that trade is a positive-sum game, and nations can only be lifted out of poverty when the whole pie grows. But this is unintuitive.

Two, Indian politics revolves around identity and patronage. The spoils of power are limited – that is indeed a zero-sum game – so you’re likely to vote for whoever can look after the interests of your in-group rather than care about the economy as a whole.

Three, voters tend to stay uninformed for good reasons, because of what Public Choice economists call Rational Ignorance. A single vote is unlikely to make a difference in an election, so why put in the effort to understand the nuances of economics and governance? Just ask, what is in it for me, and go with whatever seems to be the best answer.

Four, Politicians have a short-term horizon, geared towards winning the next election. A good policy that may take years to play out is unattractive. A policy that will win them votes in the short term is preferable.

Sadly, no Indian party has shown a willingness to aim for the long term. The Congress has produced new Gandhis, but not new ideas. And while the BJP did make some solid promises in 2014, they did not walk that talk, and have proved to be, as Arun Shourie once called them, UPA + Cow. Even the Congress is adopting the cow, in fact, so maybe the BJP will add Temple to that mix?

Benjamin Franklin once said, “Democracy is two wolves and a lamb voting on what to have for lunch.” This election season, my friends, the people of India are on the menu. You have been deveined and deboned, marinated with rhetoric, seasoned with narrative – now enter the oven and vote.

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

This is the 16th installment of The Rationalist, my column for the Times of India.

Steven Pinker, in his book Enlightenment Now, relates an old Russian joke about two peasants named Boris and Igor. They are both poor. Boris has a goat. Igor does not. One day, Igor is granted a wish by a visiting fairy. What will he wish for?

“I wish,” he says, “that Boris’s goat should die.”

The joke ends there, revealing as much about human nature as about economics. Consider the three things that happen if the fairy grants the wish. One, Boris becomes poorer. Two, Igor stays poor. Three, inequality reduces. Is any of them a good outcome?

I feel exasperated when I hear intellectuals and columnists talking about economic inequality. It is my contention that India’s problem is poverty – and that poverty and inequality are two very different things that often do not coincide.

To illustrate this, I sometimes ask this question: In which of the following countries would you rather be poor: USA or Bangladesh? The obvious answer is USA, where the poor are much better off than the poor of Bangladesh. And yet, while Bangladesh has greater poverty, the USA has higher inequality.

Indeed, take a look at the countries of the world measured by the Gini Index, which is that standard metric used to measure inequality, and you will find that USA, Hong Kong, Singapore and the United Kingdom all have greater inequality than Bangladesh, Liberia, Pakistan and Sierra Leone, which are much poorer. And yet, while the poor of Bangladesh would love to migrate to unequal USA, I don’t hear of too many people wishing to go in the opposite direction.

Indeed, people vote with their feet when it comes to choosing between poverty and inequality. All of human history is a story of migration from rural areas to cities – which have greater inequality.

If poverty and inequality are so different, why do people conflate the two? A key reason is that we tend to think of the world in zero-sum ways. For someone to win, someone else must lose. If the rich get richer, the poor must be getting poorer, and the presence of poverty must be proof of inequality.

But that’s not how the world works. The pie is not fixed. Economic growth is a positive-sum game and leads to an expansion of the pie, and everybody benefits. In absolute terms, the rich get richer, and so do the poor, often enough to come out of poverty. And so, in any growing economy, as poverty reduces, inequality tends to increase. (This is counter-intuitive, I know, so used are we to zero-sum thinking.) This is exactly what has happened in India since we liberalised parts of our economy in 1991.

Most people who complain about inequality in India are using the wrong word, and are really worried about poverty. Put a millionaire in a room with a billionaire, and no one will complain about the inequality in that room. But put a starving beggar in there, and the situation is morally objectionable. It is the poverty that makes it a problem, not the inequality.

You might think that this is just semantics, but words matter. Poverty and inequality are different phenomena with opposite solutions. You can solve for inequality by making everyone equally poor. Or you could solve for it by redistributing from the rich to the poor, as if the pie was fixed. The problem with this, as any economist will tell you, is that there is a trade-off between redistribution and growth. All redistribution comes at the cost of growing the pie – and only growth can solve the problem of poverty in a country like ours.

It has been estimated that in India, for every one percent rise in GDP, two million people come out of poverty. That is a stunning statistic. When millions of Indians don’t have enough money to eat properly or sleep with a roof over their heads, it is our moral imperative to help them rise out of poverty. The policies that will make this possible – allowing free markets, incentivising investment and job creation, removing state oppression – are likely to lead to greater inequality. So what? It is more urgent to make sure that every Indian has enough to fulfil his basic needs – what the philosopher Harry Frankfurt, in his fine book On Inequality, called the Doctrine of Sufficiency.

The elite in their airconditioned drawing rooms, and those who live in rich countries, can follow the fashions of the West and talk compassionately about inequality. India does not have that luxury.

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

This is the 22nd installment of The Rationalist, my column for the Times of India.

Trade wars are on the rise, and it’s enough to get any nationalist all het up and excited. Earlier this week, Narendra Modi’s government announced that it would start imposing tariffs on 28 US products starting today. This is a response to similar treatment towards us from the US.

There is one thing I would invite you to consider: Trump and Modi are not engaged in a war with each other. Instead, they are waging war on their own people.

Let’s unpack that a bit. Part of the reason Trump came to power is that he provided simple and wrong answers for people’s problems. He responded to the growing jobs crisis in middle America with two explanations: one, foreigners are coming and taking your jobs; two, your jobs are being shipped overseas.

Both explanations are wrong but intuitive, and they worked for Trump. (He is stupid enough that he probably did not create these narratives for votes but actually believes them.) The first of those leads to the demonising of immigrants. The second leads to a demonising of trade. Trump has acted on his rhetoric after becoming president, and a modern US version of our old ‘Indira is India’ slogan might well be, “Trump is Tariff. Tariff is Trump.”

Contrary to the fulminations of the economically illiterate, all tariffs are bad, without exception. Let me illustrate this with an example. Say there is a fictional product called Brump. A local Brump costs Rs 100. Foreign manufacturers appear and offer better Brumps at a cheaper price, say Rs 90. Consumers shift to foreign Brumps.

Manufacturers of local Brumps get angry, and form an interest group. They lobby the government – or bribe it with campaign contributions – to impose a tariff on import of Brumps. The government puts a 20-rupee tariff. The foreign Brumps now cost Rs 110, and people start buying local Brumps again. This is a good thing, right? Local businesses have been helped, and local jobs have been saved.

But this is only the seen effect. The unseen effect of this tariff is that millions of Brump buyers would have saved Rs 10-per-Brump if there were no tariffs. This money would have gone out into the economy, been part of new demand, generated more jobs. Everyone would have been better off, and the overall standard of living would have been higher.

That brings to me to an essential truth about tariffs. Every tariff is a tax on your own people. And every intervention in markets amounts to a distribution of wealth from the people at large to specific interest groups. (In other words, from the poor to the rich.) The costs of this are dispersed and invisible – what is Rs 10 to any of us? – and the benefits are large and worth fighting for: Local manufacturers of Brumps can make crores extra. Much modern politics amounts to manufacturers of Brumps buying politicians to redistribute money from us to them.

There are second-order effects of protectionism as well. When the US imposes tariffs on other countries, those countries may respond by imposing tariffs back. Raw materials for many goods made locally are imported, and as these become expensive, so do those goods. That quintessential American product, the iPhone, uses parts from 43 countries. As local products rise in price because of expensive foreign parts, prices rise, demand goes down, jobs are lost, and everyone is worse off.

Trump keeps talking about how he wants to ‘win’ at trade, but trade is not a zero-sum game. The most misunderstood term in our times is probably ‘trade-deficit’. A country has a trade deficit when it imports more than what it exports, and Trump thinks of that as a bad thing. It is not. I run a trade deficit with my domestic help and my local grocery store. I buy more from them than they do from me. That is fine, because we all benefit. It is a win-win game.

Similarly, trade between countries is really trade between the people of both countries – and people trade with each other because they are both better off. To interfere in that process is to reduce the value created in their lives. It is immoral. To modify a slogan often identified with libertarians like me, ‘Tariffs are Theft.’

These trade wars, thus, carry a touch of the absurd. Any leader who imposes tariffs is imposing a tax on his own people. Just see the chain of events: Trump taxes the American people. In retaliation, Modi taxes the Indian people. Trump raises taxes. Modi raises taxes. Nationalists in both countries cheer. Interests groups in both countries laugh their way to the bank.

What kind of idiocy is this? How long will this lose-lose game continue?

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

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.
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Hello,
I'm exploring VManager tool capabilities.

I launched a simulation with xrun, which terminates with a fatal error (`uvm_fatal actually).

Then I imported the flow session, through VManager -> Regression -> Collect Runs, linking the directory with ucm and ucd of just failed run.

VManager imports the test with following attributes:

Total Runs =1

#Passed =1

#Failed =0

What I'm missing here? It should be imported as failed test.

If I right click on flow name and choose Analyze All Runs, VManager brings me to Analysis tab and I can see only a PASSED tag in Runs subwindow.

Thank you for any help

Hi supporters,

I got the following error while I run simulation with gate netlist using Cadence Incisive (v15.20):

----

ncsim(64): 15.20-s076: (c) Copyright 1995-2019 Cadence Design Systems, Inc.
ncsim: *E,DLOALB: Design library 'tcbnxxx' not defined while reading module tcbnxxx.MAOxxx:bv (VST).
ncsim: *F,NOSIMU: Errors initializing simulation 'alu_tb' 

----

xxx: standard library name.

My netlist design uses a cell "MAOxxx". I already included the library behavior model to compile using ncverilog, there is no error while compiling. But when I run with ncsim to execute the test, I got above error.

I tried to run with other vendors such as VCS or MTI, they worked.

Please help to understand the error.

Thanks.

Hi,

I've vhdl block containing fsm . IMC not able to auto extract the state machine coded like this:

There is a intermediate state state_mux  between next_state & state.

Pls. help in guiding IMC how to recognize this FSM coding style? 

Snipped of the fsm code:

----------------------------------------------------------------------------------------------------------------------------------------------

               type state_type is (ST_IDLE, ST_ADDRESS, ST_ACK_ADDRESS, ST_READ, ST_ACK_READ, ST_WRITE, ST_ACK_WRITE, ST_IDLE_BYTE);

               signal state : state_type;

               signal state_mux : state_type;

               signal next_state : state_type;

process(state_mux, start)

         begin

               next_state <= state_mux;

               next_count <= (others => '0');

           case (state_mux) is

                 when ST_IDLE => 

                            if(start = '1') then

                                 next_state <= ST_ADDRESS;

                              end if;

            when ST_ADDRESS =>

   …………….

          when others => null;

         end case;

     end process;

process(scl_clk_n, active_rstn)

               begin

                      if(active_rstn = '0') then

                           state <= ST_IDLE after delay_f;

                  elsif(scl_clk_n'event and scl_clk_n = '1') then

                             state <= next_state after delay_f;

                            end if;

end process;

process(state, start)

               begin

                     state_mux <= state;

               if(start = '1') then

                       state_mux <= ST_IDLE;

                              end if;

               end process;

Thanks

Raghu

I'm sending encrypted HDL to a customer who will use Cadence IES for simulation and was wondering how I should go about the encryption.

Does IES support the IEEE's P1735 and if so, where can I find Cadence's public key for performing the encryption?

Or is there an alternative solution that I can use for encryption?

Hello!

I have input signal like this  ->  input  wire [ADM_NUM-1:0][1:0] m_axi_ddr_rresp.

When i want to analyze coverage from IMC  this signal not covered!

Can i collect coverage for this signal?

Hi,

I am facing this elaboration error when using Xcelium:

Command>

    xmverilog -v200x +access+r +xm64bit -f vlist -reflib plib -timescale 1ns/1ps

Log>

    xmelab: *E,CUVMUR (<name>.v,538|18): instance 'LUTP0.C GLAT3' of design unit 'tlatntscad12' is unresolved in 'worklib.LUTP0:v'.

I guess the plib was not referred to as the simulation configuration because the tlatntscad12 is included in plib.

The plib is compiled by INCISIVE 13.20 and I am using the Xcelium 19.30.

Please tell me the correct command on how to refer to the library directory compiled by different versions.

Thank you,

hi,

due to technical problem i am running simulation through terminal. Therefore, I have a Verilog file, a test bench and i have also exported from Genus synthesized netlist and sdf file. Now, how can i annotate sdf in my post-synthesis simulation using XCELIUM while using command line?

thank you

I’m not talking about carnival funhouse mirrors, but rather the different options for mirroring symbols, vias, and bond fingers in your IC Package layout. The Allegro Package Designer Plus and SiP Layout tools have two distinct styles of m...(read more)

We’ve all seen bar codes and the more modern QR codes. They’re everywhere you go – items at the grocery store, advertisements and posters, even on websites. Did you know that, with the productivity toolbox in Allegro Package Designe...(read more)

Molding caps aren’t something we talk about too frequently around here. We all know they exist, and they serve an important purpose of protecting the delicate die from potentially harsh environmental conditions. They impact how well heat can be...(read more)

Those who work in the IC Packaging design space have some unique challenges. We bridge between the IC design world (90/45-degree traces with rectangular and octagonal pins) and the PCB domain (any-angle routing, filled planes, and a multitude of pad ...(read more)

We have talked about aspects of the in-design symbol edit application mode in the past. This is the environment specific to the Allegro Package Designer layout tools allowing you to work on symbol definitions directly in the context of your layout de...(read more)

Hello, I need to ask a question regarding hierarchy in allegro schematic. I have created one but now i need to make changes to one section so that its not reflected into the other?

Here are two screen capture of Before and After Autorouting my board. Padstacks have all been revised and corrected. The Capture Schematic is correct. All Footprints have been verified after Padstack revision. a new NETLIST generation have been done after some corrections made in Capture. I have imported the new Logic. I revised my Layout Cross Section as such: TOP, GND, VCC, BOTTOM. Both VCC and GND shapes have been assigned to their respective logical GND and VCC Nets (verified). Yet, I still have the Autorouter to systematically use extra vias to make GND and VCC connections to the VCC and GND planes. Where a simple utilisation of the part padstack inner layer would have been indicated. What Im I missing ?

I am using PCB Editor v17.2-2016.

I tried to do placement by schematic page but not all pages are displayed.

Earlier, I successfully do the placement by schematic pages and it was showing all the pages. But then I decided to delete all placed components and to do placement again.

When I try to do placement by schematic page again, I noticed that only the pages that I have successfully do all the placement previously are missing.

Hi everyone! I'm working on a small battery powered PCB which will fit inside a small plastic "hockey puck" container. A number of these "pucks" will be sold together with a "charging doc" which will store and charge the pucks when not in use.

I'm trying to work out the best way to charge the battery. I'm thinking of having metal "pads" on the rr.com puck that pass through the puck's plastic shell and then make contact with the PCB on the inside, and having a similar system on the charging dock. I'm thinking of having SMD "contact sprints" mounted to the underside of the PCB and have these mate against metal pins that protrude through the puck, but it's the later of which I'm struggling to find. For a visual, think about "restaurant pagers" and how they charge.

Hi, I am in the middle of a design and had no problem going back and forth between schematics and layout. Now I am getting the error message below. I am using Cadence 17.2.

ERROR: Layout database has probably been reverted to an earlier version than that, which was used in the latest flow or the schematic database was synchronized with another board.

The basecopy file generated by the last back-to-front flow not found.

ERROR: Layout database has probably been reverted to an earlier version than that, which was used in the latest flow or the schematic database was synchronized with another board.

The basecopy file generated by the last back-to-front flow not found.

Error: CMFBC-1: The schematic and the layout constraints were not synchronized as the changes done since the last sync up could not be reconciled. Syncing the current version of the schematic or layout databases with a previous version would result in this issue. The  constraint difference report is displayed.

Continuing with "changes-only" processing may result in incorrect constraint updates.

Thanks for your input

Claudia

I've redesigned a custom TO220FLAT Package

First I created a TO220shape.ssm  with PCB Editor. Then I created a surface mount T220build.pad in Padstack Editor using TO220shape.ssm. Then I created a TO220FLAT.psm in PCB Editor. I placed 3 Connect pins and 9 Mechanical pins for the TO220 TAB, using standard through-hole pads for better current handling.

Adding those Mechanical pins created many DRC errors caused by the proximity of those pads attached to the TO220shape.

Thru Pin to SMD Pin Spacing (-200.0 0.0) 5 MIL OVERLAP DEFAULT NET SPACING CONSTRAINTS Mechanical Pin "Pad50sq30d" Pin "T220build, 2"

I corrected the situation (so I though) by Waiving those DRC errors, thinking that they could not cause any problem and because that’s what I want, i.e.: 9 through-holes under the TO220 device. The idea being that when this device is mounted flat on the PCB it could carry lots of current via 9 pads that could make a good high current conductor to inner layers.

I then saved the Package and updated all related footprint schematic parts  in Capture. Created a new Netlist. Then I imported the new logic into PCB Editor to reflect that change. When the File > Import > Logic is finished I get no feedback error! (which, for me is a substantial achievement in itself)

Now, in the Design Window I see all those DRC errors popping up again, despite the fact that I waived those DRCs back in the Padstack edition. If I run a Design Rule Check (DRC) Report I will see all those DRC listed again. Now, I understand that I can go ahead and waive all those DRCs (100 in total) but I’m thinking there is got to be a better way of doing this.

Please, any advise is welcome. Thanks

Hi All,

I've just about to finish my first PCB layout, and I want to understand some 2 issues better:

1. Soldermask layer: when exactly do we want to define for some SMT pad (say at Pad Designer tool), to have soldermask top and when we want to define solermask bottom? 

if it's a TH pad, I guess we always want to define both layers soldermask (top, bottom), because the pads are crossing all the layers. However, if it's a SMT pad, which SM we want?

2. Pastemask layer: is this layer necessary for the gerber files generation, when we have SMT components in our circuit?

And again, when we define for a TH/SMT pads pastemask top, and when Pastemask bottom?

Thanks!

Hello All,

I'm currently using OrCAD PCB Designer Professional w/ PSpice (version 16.6-2015).  In the 'Design Object Find Filter' side bar, all options are grayed out and unselectable.  I did attempt to 'Reset UI to Cadence Default' without any luck.  A colleague has no issues with the identical file on his computer.  Any guidance would be much appreciated.  Thanks!

George

Hi everybody,

I've created a symbol with custom pad shapes. Everything looks correct in the symbol editor.

And the 3d view looks correct (upside down to show placement)

But when I try to place it on the pcb the 2 "T" shaped pads aren't in the correct location.

I have the pad shape centered on the pad...

with no offset on the padstack editor.

Does anybody know how to fix this?

Thank you!

Hi,

I have a new customer that uses Allegro Design entry HDL for the schematic and have a few questions.

1. How do you get pin/gate swaps into the symbols in the schematic ?

2. How do you transfer them to the pcb editor ?

3. How do you back annotate the swaps from the pcb editor to the schematic ?

4. How do you stop the export/Import physical from updating the constraints in the pcb file ? 

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

Please include a brief summary of how to use it.

Hi, I am uploading a register class, which can be used for modeling hardware registers. I am uploading the source code and examples on how to run it. I also have a user guide which has all the APIs listed and explained. The user guide is ARV.pdf in the attached tar file. I have named the class ARV, which stands for Architect's Register View. It has got very good randomization and coverage features. Users have told me that its better than RAL. You can download it from http://verisilica.info/ARV.php
. There is a limit of 750KB in this cadence website. The ARV file is 4MB. That is why, I am uploading it at this site. I have a big pdf documentation and a doxygen documentation there. That is the reason for the bigger file size. The password to open the ZIP file is ovm_arv. I hope, everyone will use these classes.

Please contact me for any help.
Regards ANil

I've heard lots of people asking for a way to generate Makefiles for Specman code, and it seems there are some who don't use "irun" which takes care of this automatically. So I wrote this little utility to build a basic Makefile based on the compiled and loaded e code.

It's really easy to use: at any time load the snmakedeps.e into Specman, and use "write makefile <name> [-ignore_test]".
This will dump a Makefile with a set of variables corresponding to the loaded packages, and targets to build any compiled modules.
Using -ignore_test will avoid having the test file in the Makefile, in case you switch tests often (who doesn't?).

It also writes a stub target so you can do "make stub_ncvlog" or "make stub vhdl" etc.

The targets are pretty basic, I thought it was more useful to #include this into the main Makefile and define your own more complex targets / dependencies as required.

The package uses the "reflection" facility of the e language, which is now documented since Specman 8.1, so you can extend this utility if you want (please share any enhancements you make).

 Enjoy! :-)

Steve.