Saturday 23 May 2015

Verification Management: Scripting makes Life Easier

Increase in demand for high quality Verification IP’s and shortening design cycles puts pressure on IP houses to leverage automation in verification process. This shows that the management of data and process are important to an efficient and productive verification environment. Using a built in system like Questa VRM (Verification Run Manager) and Cadence Emanager can give Verification Engineers maximum throughput and the benefits of automation but companies who can’t afford licenses for a long period can develop their own automation scripts for the verification process.

Often automation scripts are heavily scripted by an individual and are carried out from project to project, majority of the team don’t know what actually the script is doing and they just simply use it until and unless it works fine for them. To get the full benefits of the automation script, an individual needs to understand what actually the script does.

You may be asking me why should I make the effort of learning how to script? The Simple answer is it will likely start to impact our job in the near future if we do not. As systems get increasingly larger and more complex, the time spent in verification process consumes an increasing sum of time.

Two main justifying reasons to script a task:

1)     It is repetitive, time consuming or overly tedious
2)     Human Error must be reduced to as close to zero as possible


We developed an automation script in cshell that performs 70% of functionality what actually a built in Verification management does. Our script has the ability to automate management of seeds for constrained random tests, re-run failed tests automatically perhaps with more debug visibility, merge coverage across multiple runs, manage tool time-outs, to name just a few functions.

The features available in this script include:

·         Single test case run with coverage on and off.
·         Multiple test case run with coverage on and off.
·         Single test case run with particular seed number.
·         Graph analysis of regression results.
·         Regression Results distribution to team.
All required options can be passed through command line or through a configuration file. Some of these switches include
<script_name> <layer>  : Runs Regression with functional coverage enable.

Note: <layer> specifies either protocol , link ,physical layer specific tests to  USB3.

<script_name>  <layer> cov_off : Runs Regression with functional coverage off.

<script_name>  <test_name>  cov_off  re_run seed <seed_number>: Re-run a single test case with a particular seed number.

A set of analysis has been performed on the scripts and observed that the users Productivity is being boosted across many different aspects of verification management including capacity, performance, resource usage, turn-around time, preparation, maintenance etc...In conclusion, the user has to be careful in selecting the options based upon his requirements.

So would you like to try to use scripts to reduce verification efforts? I would like to hear from all of you.

Saturday 16 May 2015

Is Moore’s Law really dead?

Thanks for viewing my earlier post and suggesting accordingly.

      Figure 1 :  Audience Statistics 
As discussed in the my earlier post Moore’s statement is an observation on the number of transistors on a chip that increases exponentially  and he didn't mention on the speed , Architecture ,size and cost of the chip.

Is Moore’s Law really dead?

The short answer for now, not yet, but it might be going to end in near future. Recently Researchers have warned that the era of exponent graph may come to end , I don’t want to argue on the forecast but we need to focus on other alternatives such as.

     1.       New Material to Replace silicon.
     2.       Advance Manufacturer Techniques.
     3.       3D Transistors. ( I will discuss in-depth in future posts)

Figure 2 :  Appreciation by NXP for my Poster Presentation on 3D Transistors and Bio-Neuro Chips in  year 2011 

The law of physics doesn't allow chip size to shrink below to an extent , Researchers predicts that it might shrink up to 5 nm by 2020.

According to me the day when chip maker can’t get returns on the billions he invested that is the end of Moore’s prediction.

Long Live Moore's Prediction.

Thanks in advance for Reading the Post.

 Next i will be Posting few articles on UVM along with my friends and colleagues with subject (UVM with Vikas). 

Stay  Tuned ...

Sunday 3 May 2015

Moore’s Law Marks 50 years

This Year Moore’s Law Marks 50 years. Gordon More , the co-founder of Intel made this Prediction in 1965, that the number of transistors will double every year, while the cost of production remains same.

Gordon More

Does this is an Observation or Law or Rule ?

            Does this as an end ?

                     Does Companies sustain without this ?

    Let us discuss.

1.           Observation or Law or Rule :  Law or Rule doesn't change but Observations can. From 1965 to 1975 the number of transistors doubled every year but  from 2008 it slowed down to around 2 to 3 years approximately. Even Gordon More didn't call it has a Law, he said that things changes exponentially.  So this is an Observation.

                                                                                   Shrinking Feature Size

2.         Will Moore’s Law has an Expiry Date : As per nature everything has an end, what about Moore’s law ? Does it has an end ? Then how companies sustain? Does a new technology has to be evolved or is there an alternative solution ? Researchers predicted that Transistor shrinkage can happen only up to 2021? What next ? Instead of segueing Transistors chip makers are coming up with 3D Transistors i.e. stacking Transistors in to Layers. There is a saying in real estate; when land get expensive, multi-storied buildings are the alternative solution.

   3D Architecture

                                                   Gordon More's Initial Sketch of his Observation

In my next blog I will come up with the Reasons why Moore’s Law need to end ? and the devil factors which is going to make it buried.I will also Discuss on 3D Architecture and its Market Trends in the following post.

Thanks for Reading and suggestions are Welcome ..