Learn how Xcelium PowerPlayback App enables the massively parallel Xcelium replay of waveforms for glitch-accurate power estimation of multi-billion gate SoC designs.(read more)

To stay ahead in competition in chip design real-time collaborations ensure traceability, speedy innovations at reduced the cost.(read more)

Xcelium Simulator has been in the industry for years and is the leading high-performance simulation platform. As designs are getting more and more complex and verification is taking longer than ever, the need of the hour is plug-and-play apps that ar...(read more)

It has become challenging to ensure that the designs are complete, correct, and adhere to necessary coding rules before handing them off for RTL verification and implementation. RTL Designer Signoff Solution from Cadence helps the user identify RTL bugs at a very early development stage, saving a lot of effort and cost for the design and verification team. Our reputed customers have confirmed that using RTL signoff for their design IP helped save up to 4 weeks and reduce the late-stage RTL changes by up to 80%.(read more)

In a network containing multiple nodes, the need for synchronization between the various nodes is not just instrumental but also a complicated and highly complex process. This process becomes even more tricky if we synchronize the clocks between the Manager and the Peripheral. As we know, in a real-time network, some of the nodes would behave like Managers while some would be a Peripheral. If we must make the communication process smooth, then the local clocks of these nodes must be synchronized. 

The problem with this synchronization is that we have the clock running in the Manager as well. If we send the value of the Manager clock to the Peripheral, the synchronization doesn’t happen as we have a propagation delay of the messages, along with the propagation delay of the electronic circuits of Manager and the Peripheral.  

The cherry on the cake is that these electronic circuit propagation delays are not random and remain constant, so we can add a time offset to it to match the clock. To tackle this challenge, IEEE has come up with a protocol named “Precision Timing Protocol.” 

Operation of PTP: 

To synchronize the clocks, a Sync message is sent by the Manager to the Peripheral, which then timestamps the receiving time of the same. Following this, a ‘Follow up’ message is issued by the Manager stating the timestamp at which the Sync message was sent. 

The Peripheral then finds the difference between the two values and adds this to its current time. After this, the time difference between the Manager and the Peripheral narrows down to only the propagation delay of the messages.  

To overcome this, the Peripheral issues a ‘Delay Request’ to the Manager, and the Manager, in turn, issues a ‘Delay Response.’ Both these messages have the timestamp of when they were issued. The time at which they are received is then noted. Since two messages are sent, one from the Peripheral and the other from the Manager, there are two propagation delays. Then half of this value is our propagation delay. 

The Peripheral then adds this propagation delay to its clock, and hence the clock gets synchronized. 

Advantages of PTP: 

1. It provides accurate time stamping. 
2. It is a well-known clock synchronization protocol. 
3. It provides intensified security inside the premises. 
4. It provides the possibility of setting coordinated actions and synchronized communication. 

There are various versions of PTP that have been developed over time, namely PTPv1, PTPv2, PTPv2_1, and the latest PTP-AS. 

Cadence Verification IP for Ethernet is available to support the newer version of PTP, allowing simulation of the device for efficient IP, SoC, and system-level design verification. Semiconductor companies can start using it to fully verify their controller design and achieve functional verification closure on it within no time. 

The rising customer expectations, intermingling fields and high performance needs can be satisfied with the system based design. An intelligent Systems Design strategy can offer a quicker route to an optimum design and helps to increase designers' productivity and analyzes efficiency by providing the ability to explore the entire design space. Cadence Intelligent System Strategy enables a system design revolution and reduces project schedules with optimized continuous integration.(read more)

One of the key goals for USB4 is to retain compatibility with the existing ecosystem of USB3.2, USB 2.0 and Thunderbolt  products, and the resulting connection scales to the best mutual capability of the devices being connected. USB4 is designed to work with older versions of USB and Thunderbolt . USB4 Fabric support high throughput interconnects of 10 Gbps (for Gen 2) and 20 Gbps (for Gen 3) and supports Thunderbolt 3-compatible rates of 10.3125 Gbps (for Gen 2) and 20.625 Gbps (for Gen 3). It becomes very important to verify the Thunderbolt  backward compatibility with the designs. Though the support of USB4 Interoperability with Thunderbolt  3 (TBT3) is optional in USB4 host or USB4 peripheral device and required USB4 Hub and USB4 Based Dock but it is very essential to work in the existing ecosystem. 

Few Main features of USB4 Interoperability with Thunderbolt  3 (TBT3) Systems

• Support for Bi-Directional Pins & Retimers: TBT3 Active Cables can contain two bidirectional Re-timers which have the capability to send AT Responses on its RX channel. Router connected directly to such Retimer needs to support A Router that is connected directly to a bidirectional Re-timer shall support reception of Transactions on both TX and RX channels. 

• Bounce Mechanism: This feature is used by Router to access the Register Space of a Cable Re-timer that can only be accessed by its Link Partner.
• Asymmetric Negotiation: The Router which connects with Cable Retimers needs to follow Asymmetric TxFFE in Phase 5 of Lane Initialization. 
• USB4 Link Transitions: In TBT3 mode, the configuration of two independent Single Lane Links can be used non-transient state or Single Lane Link just using the Lane1 Adapter.

Cadence has a mature USB4 Verification IP solution that can help in the verification of USB4 designs with TBT3. Cadence has taken an active part in the Cairo group that defined the USB4 specification and has created a comprehensive Verification IP that is being used by multiple members. If you plan to have a USB4-compatible design, you can reduce the risk of adopting new technology by using our proven and mature USB4 Verification IP. Please contact your Cadence local account team, for more details.

New IC packaging workflows in Cadence Allegro X layout tools allow you to follow a guided path from starting a design through final manufacturing. The path is there to ensure that you don’t miss steps and perform actions in the optimal order. W...(read more)

OrCAD X is the next-generation integrated PCB design platform. It brings to you a powerful cloud-enabled design solution that includes design and library data management integrated with the proven PCB design and analysis product portfolio of Cad...(read more)

Introduction

Multiphysics is an integral part of the concepts around digital twins. In this post, I want to discuss the mechanical aspects of multiphysics in system simulations, which are critical for 3D-IC, multi-die, and chiplet design.

The physical world in which we live is growing ever more electrified. Think of the transformation that the cell phone has brought into our lives, as has the present-day migration to electronic vehicles (EVs). These products are not only feats of electronic engineering but of mechanical as well, as the electronics find themselves in new and novel forms such as foldable phones and flying cars (eVOTLs). Here, engineering domains must co-exist and collaborate to bring about the best end products possible.

Start with the electronics—chips, chiplets, IC packaging, PCB, and modules. But now put these into a new form factor that can be dropped or submerged in water or accelerated along a highway. What about drop testing, aerodynamics, and aeroacoustics? These largely computational fluid dynamics (CFD) and/or mechanical multiphysics phenomena must also be accounted for. And then how does the drop testing impact the electrical performance? The world of electronics and its vast array of end products is pushing us beyond pure electrical engineering to be more broadly minded and develop not only heterogeneous products but heterogeneous engineering teams as well.

Cadence's Unique Expertise

It's at this crossroad of complexity and electronic proliferation that Cadence shines. Let's take, for example, the latest push for higher-performing high-bandwidth memory (HBM) devices and AI data center expansion. These technologies are growing from several layers to 12, and I can't emphasize enough the importance of teamwork and integrated solutions in tackling the challenges of advanced packaging technologies and how collaboration is shaping the future of semiconductor innovation and paving the way for cutting-edge developments in the industry.

These layered electronics are powered, and power creates heat. Heat needs to be understood, and thus, the thermal integrity issues uncovered along the way must be addressed. However, electronic thermal issues are just the first domino in a chain of interdependencies. What about the thermal stress and warpage that can be caused by the powering of these stacked devices? How does that then lend to mechanical stress and even material fatigue as the temperature cycles from high to low and back through the use of the electronic device? This is just one example in a long list of many...

Cadence Multiphysics Analysis Offerings

The confluence of electrical, mechanical, and CFD is exactly why Cadence expanded into multiphysics at a significant rate starting in 2019 with the announcement of the Clarity 3D Solver and Celsius Thermal Solver products for electromagnetic (EM) and thermal multiphysics system simulations. Recent acquisitions of Numeca, Pointwise, and Cascade (now branded within Cadence as the Fidelity CFD Platform) as well as Future Facilities (now the Cadence Reality Digital Twin product line) are all adding CFD expertise. The recent addition of Beta CAE brings mechanical multiphysics to the suite of solutions available from Cadence. The full breadth of these multiphysics system analyses, spanning EM, thermal, signal integrity/power integrity (SI/PI), CFD, and now mechanical, creates a platform for digital twinning across a wide array of applications. You can learn more by viewing Cadence's Reality Digital Twin platform launch on the keynote stage at NVIDIA's GTC in March, as well as this Designed with Cadence video: NV5, NVIDIA, and Cadence Collaboration Optimizes Data Centers.

Conclusion

Ever more sophisticated electronic designs are in demand to fulfill the needs of tomorrow's technologies, driving a convergence of electrical and mechanical aspects of multiphysics in system simulations. To successfully produce the exciting new products of the future, both domains must be able to collaborate effectively and efficiently. Cadence is fully committed to developing and providing our customers with the software products they need to enable this electrical/mechanical evolution. From EM, to thermal, to SI/PI, CFD, and mechanical, Cadence is enabling digital twinning across a wide array of applications that are forging pathways to the future.

For more information on Cadence's multiphysics system analysis offerings, visit our webpage and download our brochure.

Community engagement is a dynamic concept that does not adhere to a singular, universal approach. Its various forms, methods, and objectives can vary significantly depending on the specific context, goals, and desired outcomes. Whether you seek assis...(read more)

Power network design and analysis of 3D-ICs is a major challenge due to the complex nature and large size of the power network. In addition, designers must deal with the complexity of routing power through the interposer, multiple dies, through-silicon vias (TSVs), and through-dielectric vias (TDVs).
Cadence’s Integrity 3D-IC Platform and Voltus IC Power Integrity Solution provide a fully integrated solution for early planning and analysis of 3D-IC power networks, 3D-IC chip-centric power integrity signoff, and hierarchical methods that significantly improve capacity and performance of power integrity (PI) signoff while maintaining a very high level of accuracy at signoff. This blog summarizes the typical design challenges faced by today’s 3D-IC designers, as discussed in our recent webinar, “Addressing 3D-IC Power Integrity Design Challenges.” Please click here to view the full webinar.

Major Trends in Advanced Chip Design

From chips to chiplets, stacked die, 3D-ICs, and more, three major trends are impacting advanced semiconductor packaging design. The first is heterogenous integration, which we define as a disaggregated approach to designing systems on chip (SoCs) from multiple chiplets. This approach is similar to system-in-package (SiP) design, except that instead of integrating multiple bare die – including 3D stacking – on a single substrate, multiple IPs are integrated in the form of chiplets on a single substrate.

The second major trend is around new silicon manufacturing techniques that leverage silicon vias (TSVs) and high-density fanout RDL. These advancements mean that silicon is becoming a more attractive material for packaging, especially when high bandwidth and form factor become key attributes in the end design. This brings new design and verification challenges to most packaging engineers who typically work with organic and ceramic substrate materials.

Finally, on the ecosystem side, all the large semiconductor foundries now offer their own versions of advanced packaging. This brings new ways of supporting design teams with technologies like reference flows and PDKs, concepts that have typically been lacking in the packaging community. Cadence has worked with many of the leading foundries and outsourced semiconductor assembly and test facilities (OSATs) to develop multi-chip(let) packaging reference flows and package assembly design kits. The downside is that, with the time restrictions designers are under today, there isn’t enough time to simulate the details of these flows and PDKs further.

For those who must make the best electro/thermal/physical decisions to achieve the best power/performance/area/cost (PPAC), factors can include accurate die size estimations, thermal feasibility, die-to-die interconnect planning, interposer planning (silicon/organic), front-to-front and front-to-back (F2F/F2B) planning, layer stack and electromigration/ IR drop (EMIR)/TSV planning, IO bandwidth feasibility, and system-level architecture selection.

3D-IC Power Network Design and Analysis

The key to success in 3D-IC design is early power integrity planning and analysis. Cadence’s Integrity 3D-IC platform is a high-capacity 3D-IC platform that enables 3D design planning, implementation, and system analysis in a single, unified cockpit. Cadence’s Voltus IC Power Integrity Solution is a comprehensive full chip electromigration, IR drop, and power analysis solution. With its fully distributed architecture and hierarchical analysis capabilities, Voltus provides very fast analysis and has the capacity to handle the largest designs in the industry. Typically, 3D-IC PDN design and analysis is performed in four phases, as shown in Figure 1.

Phase 1 - Perform early power delivery network (PDN) exploration with each fabric’s PDN cascaded in system PI with early circuit models.

Phase 2 – Plan 3D-IC PDNs in Cadence’s Integrity 3D-IC platform, including micro bumps, TSVs, and through dielectric vias (TDVs), power grid synthesis for dies, and early rail analysis and optimization.

Phase 3 – Perform full chip-centric signoff in Voltus with detailed die, interposer, and package models, including chip die models, while keeping some dies flat.

Phase 4 – Perform full system-level signoff with Cadence’s Sigrity SystemPI using detailed extracted package models from Sigrity XtractIM, board models from Sigrity PowerSI or Clarity 3D Solver, interposer models from XtractIM or Voltus, and chip power models from Voltus.

Figure 1. 3D-IC PDN design and analysis phases

3D-IC Chip-Centric Signoff

The integration of Integrity 3D-IC and Voltus enables chip-centric early analysis and signoff. Figure 2 and Figure 3 highlight the chip centric early PI optimization and signoff flows. In early analysis, the on-chip power networks are synthesized, and the micro bumps and TSVs can be placed and optimized. In the signoff stage, all the detailed design data is used for power analysis, and detailed models are extracted and used for package, interposer, and on-die power networks.

Figure 2. Early chip-centric PI analysis and optimization flow

Figure 3. Chip-centric 3D-IC PI signoff

Hierarchical 3D-IC PI Analysis

To improve the capacity and performance of 3D-IC PI analysis, Voltus enables hierarchical analysis using chiplet models. Chiplet models can be reduced chip models in spice format or more accurate xPGV models which are highly accurate proprietary models generated by Voltus. With xPGV models, the hierarchical PI analysis has almost the same accuracy as flat analysis but offers 10X or higher benefit in runtime and memory requirements.

Conclusion

This blog has highlighted the major design trends enabled by advanced 3D packaging and the design challenges arising from these advancements. The design of power delivery networks is one of these major challenges. We have discussed Cadence solutions to overcome this PI challenge. To learn more, view our recent webinar, "Addressing 3D-IC Power Integrity Design Challenges" and visit the Voltus web page.

When it comes to system integration, PCB designers need to collaborate with the signal analysis or integrity team to run pre-route or post-route analysis and modify constraints, floorplan, or topology based on the results. Allegro PCB Edito...(read more)

Melika Roshandell, Cadence product marketing director for the Celsius Thermal Solver, recently published an article in Designing Electronics discussing how the use of modern thermal analysis techniques can help engineers meet the challenges of today’s complex electronic designs, which require ever more functionality and performance to meet consumer demand.

Today’s modern electronic designs require ever more functionality and performance to meet consumer demand. These requirements make scaling traditional, flat, 2D-ICs very challenging. With the recent introduction of 3D-ICs into the electronic design industry, IC vendors need to optimize the performance and cost of their devices while also taking advantage of the ability to combine heterogeneous technologies and nodes into a single package. While this greatly advances IC technology, 3D-IC design brings about its own unique challenges and complexities, a major one of which is thermal management.

To overcome thermal management issues, a thermal solution that can handle the complexity of the entire design efficiently and without any simplification is necessary. However, because of the nature of 3D-ICs, the typical point tool approach that dissects the design space into subsections cannot adequately address this need. This approach also creates a longer turnaround time, which can impact critical decision-making to optimize design performance. A more effective solution is to utilize a solver that not only can import the entire package, PCB, and chiplets but also offers high performance to run the entire analysis in a timely manner.

Celsius Thermal Management Solutions

Cadence offers the Celsius Thermal Solver, a unique technology integrated with both IC and package design tools such as the Cadence Innovus Implementation System, Allegro PCB Designer, and Voltus IC Power Integrity Solution. The Celsius Thermal Solver is the first complete electrothermal co-simulation solution for the full hierarchy of electronic systems from ICs to physical enclosures. Based on a production-proven, massively parallel architecture, the Celsius Thermal Solver also provides end-to-end capabilities for both in-design and signoff methodologies and delivers up to 10X faster performance than legacy solutions without sacrificing accuracy.

By combining finite element analysis (FEA) for solid structures with computational fluid dynamics (CFD) for fluids (both liquid and gas, as well as airflow), designers can perform complete system analysis in a single tool. For PCB and IC packaging, engineering teams can combine electrical and thermal analysis and simulate the flow of both current and heat for a more accurate system-level thermal simulation than can be achieved using legacy tools. In addition, both static (steady-state) and dynamic (transient) electrical-thermal co-simulations can be performed based on the actual flow of electrical power in advanced 3D structures, providing visibility into real-world system behavior.

Designers are already co-simulating the Celsius Thermal Solver with Celsius EC Solver (formerly Future Facilities’ 6SigmaET electronics thermal simulation software), which provides state-of-the-art intelligence, automation, and accuracy. The combined workflow that ties Celsius FEA thermal analysis with Celsius EC Solver CFD results in even higher-accuracy models of electronics equipment, allowing engineers to test their designs through thermal simulations and mitigate thermal design risks.

Conclusion

As systems become more densely populated with heat-dissipating electronics, the operating temperatures of those devices impact reliability (device lifetime) and performance. Thermal analysis gives designers an understanding of device operating temperatures related to power dissipation, and that temperature information can be introduced into an electrothermal model to predict the impact on device performance. The robust capabilities in modern thermal management software enable new system analyses and design insights. This empowers electrical design teams to detect and mitigate thermal issues early in the design process—reducing electronic system development iterations and costs and shortening time to market.

To learn more about Cadence thermal analysis products, visit the Celsius Thermal Solver product page and download the Cadence Multiphysics Systems Analysis Product Portfolio.

Cadence is super excited to announce SPB 23.1 release —Your freedom to design boldly!  

These tools help engineers build better PCBs faster with the new 3D engine and optimized interface.  

We have been hard at work to bring you this release and believe that it will help you take control of the PCB design process with the powerful new features in Allegro X APD like: 

• Packaging Support in 3DX Canvas 

• 3DX Wire DRCs 

• Aligning Components by Offset 

• Text Wizard Enhancements 

• Device File Reuse for Existing Components for Netlist and Logic Import 

Watch this space to know all about What’s New in SPB 23.1.  

Regards 

Team PCBTech 

Cadence Design System 

For individuals, small businesses, or teams, START YOUR FREE TRIAL. 

Does anyone know how to not include a pbar in a constraint manager analysis? I have some relative delay constraints applied on a group of differential nets. When I analyze the design these all show an error. If I delete the plating bar from the design they are all passing. The plating bar gets generated on the Substrate Geometry / Plating_Bar class. I understand that I could just delete the plating bar to verify the constraint but the issue is when I archive this design I would like it to be clean meaning it is in the final state for manufacturing AND passing all constraints according to design reviews.

Anyone have an idea? 

Thank you!

Starting SPB 23.1, Allegro Package Designer Plus (APD+) has been rebranded as Allegro X Advanced Package Designer (Allegro X APD).

The splash screen for Allegro X APD will appear as shown below, instead of showing APD+ 2023:

For the Windows Start menu in 23.1, it will display as Allegro X APD 2023 instead of APD+ 2023, as shown below

23.1 Start menu 

In the Product Choices window for 23.1, you will see Allegro X Advanced Package Designer in the place of Allegro Package Designer +, as shown below: 

23.1 product title

Starting SPB 23.1, Allegro X APD lets you import/export the symbol and component properties by using Die Text-In/Out wizards. 

Exporting the symbol 

You can export the symbol by using File > Export > Die Text-Out Wizard. 

In the Die Text-Out Wizard window, you can see the newly added options, that is, Component Properties and Symbol Properties. 

This entire information including the properties will be saved in a text file. 

Importing the symbol 

You can import the same text file in Allegro X APD by using Die Text-In Wizard. 

Choose the text file you want to import. 

Symbol properties added in the text file will be visible in the Die Text-In Wizard window. 

At times, there might arise a condition in the design where you need to push the net of selected pins to all its physically connected objects. For example, a few pins are updated with a new net, and it is required to push the new net to all its connected objects. At times, you might update the die or copy routing to other components, when a portion of routing gets the wrong net.

To propagate the net of the pin to all its physically connected objects, Allegro X APD uses the standalone command, Push Connectivity.

You can call the command through Logic > Push Connectivity.

Alternately, you can use the push connectivity command at the command line. Once the command is active, it lets you select pins or symbols that will be used to push net connectivity to all connected objects.

Presently, dynamic shapes and filled rectangles are not considered as part of connectivity. Static shapes are supported.

hello, help me!

There are many change in the bump design. I want to design bump by APD.

The bump(die) is a stagger , create it by die generator. 

Because，the pin is not isometric. In order to RDL routing, so the bump is not isometric.

I move the symbol pin in APD symbol edit（as show in the picture）,  and selected symbol RBM write device file, write library symbol.

Export the bga text( bga text out) ,But the bump is not modified, the bump is still stagger.

Can you help me!

pitch2> pitch1

thanks

The vision manager is good tool for routing check. but no quickly or effective  tool to fix or optimize this  problems to be optimized.

For example, parallel Gap less than preferred, min seg/Arc length,uncoupled diff-pair segs，and so on.

I only know use spread between voids to fix the non-optimized segs. in fact it is inefficient.

the parallel gap less than preferred is only to slice evry trace, its inefficient.

If i set the paraller gap less than 50um, Is there any tool to quickly fix these problems（gap less than 50um）?

For other problems，i can use tool to quickly fix the min seg/Arc length，uncoupled diff pair segs，accoding to select by polygon or select  by windows.

By default, a dielectric must separate each pair of conductor layers in the cross-section of a design. In rare cases, this does not represent the real, manufactured substrate.

If your design requires you to have conductor layers that are not separated by a dielectric (such as, for half-etch designs), there is a variable that needs to be set in Allegro X APD. You must set this by enabling the variable icp_allow_adjacent_conductors. This entry, and its location in the User Preferences Editor, are shown in the following image.

The Objects on adjacent conductor layers do not electrically connect together, automatically. A via must be used to establish the inter-layer connections.

When enabling this option, it is recommended to exercise caution because excluding dielectric layers from your cross-section can lead to inaccurate calculations, including the calculations for signal integrity and via heights. It is important that your cross-section accurately reflect the finished product to ensure the most accurate results possible. Any dielectric layers present in the manufactured part need to be in the cross-section for accurate extraction, 3D viewing, and so on.

Let us know your comments on the various designs that would require adjacent conductor layers.

Hi，

Can you tell me which setting is causing this?

In the general edit. I try slide via to other position. but the slide is wrong.

in the cm，i set pad-pad connect is all allowed，and i turn off via to pad spacing in the same net spacing. only turn on via to via spacing in the same net spacing，set to via to via spacing =0.

default the via is closer to the pad edge, I think the correct location is show in the pic2.

Hello, SKILL experts. 

I'm studying SKILL language to build some useful function in APD+.

Now, I want to execute 'Import Sub-drawing' function in new form.

But I cannot find how to do execute APD+ embedded function in a field of new form. 

Has anyone experienced this or idea to solve this problem? 

When things go wrong with your package design flow, it can sometimes be difficult to understand the cause of the issue. This can be something like a die component is wrongly identified as a BGA, a via stack has an alignment issue, or there are duplicate bondwires. These are just a few examples of issues; there can be many more. When interactive messages and log files do not help determine the problem, the Package Design Integrity Check tool becomes very handy. This feature lets you run integrity checks, which ensures that the database is configured correctly. 

To invoke the command from Allegro X Advanced Package Designer, use the Tools > Package Design Integrity menu. 

Or type package integrity at the Command  prompt. 

The Package Design Integrity Checks dialog box includes all categories and checks currently registered for the currently running product. You can enable all these categories and checks or only the one that you want to run. This utility can fix errors automatically (where possible). Errors and warnings are written to the “package_design_check.log” file.  

The utility can also be extended with your own custom rules based on your specific flows and needs. 

Display Stream Compression (DSC) is a lossless or near-lossless image compression standard developed by the Video Electronics Standards Association (VESA) for reducing the bandwidth required to transmit high-resolution video and images. DSC compresses video streams in real-time, allowing for higher resolutions, refresh rates, and color depths while minimizing the data load on transmission interfaces such as DisplayPort, HDMI, and embedded display interfaces.

Why Is DSC Needed?

In the ever-evolving landscape of display technology, the pursuit of higher resolutions and better visual quality is relentless. As display capabilities advance, so do the challenges of managing the immense amounts of data required to drive these high-performance screens. This is where DSC steps in. DSC is designed to address the challenges of transmitting ultra-high-definition content without sacrificing quality or performance. As displays grow in resolution and capability, the amount of data they need to transmit increases exponentially. DSC addresses these issues by compressing video streams in real-time, significantly reducing the bandwidth needed while preserving image quality.
 

DSC Use in End-to-end System

DSC Key Features

• Encoding tools:
  • Modified Median-Adaptive Prediction (MMAP)
  • Block Prediction (BP)
  • Midpoint Prediction (MPP)
  • Indexed color history (ICH)
  • Entropy coding using delta size unit-variable length coding (DSU-VLC)

• The DSC bitstream and decoding process are designed to facilitate the decoding of 3 pixels/clock in practical hardware decoder implementations. Hardware encoder implementations are possible at 1 pixel/clock.
• DSC uses an intra-frame, line-based coding algorithm, which results in very low latency for encoding and decoding.

DSC encoding algorithm
 

• Compression can be done to a fractional bpp. The compressed bits per pixel ranges from 6 to 63.9375.
• For validation/compliance certification of DSC compression and decompression engines, cyclic redundancy checks (CRCs) are used to verify the correctness of the bitstream and the reconstructed image.
• DSC supports more color bit depths, including 8, 10, 12, 14, and 16 bpc.
• DSC supports RGB and YCbCr input format, supporting 4:4:4, 4:2:2, and 4:2:0 sampling.
• Maximum decompressor-supported bits/pixel values are as listed in the Maximum Allowed Bit Rate column in the table below

• DP DSC Source device shall program the bit rate within the range of Minimum Allowed Bit Rate column in the table:

Summary

Display Stream Compression (DSC) is a technology used in DisplayPort to enable higher resolutions and refresh rates while maintaining high image quality. It works by compressing the video data transmitted from the source to the display, effectively reducing the bandwidth required. DSC uses a visually lossless algorithm, meaning that the compression is designed to be imperceptible to the human eye, preserving the fidelity of the image. This technology allows for smoother, more detailed visuals at higher resolutions, such as 4K or 8K, without requiring a significant increase in data bandwidth.

More Information

• Cadence has a very mature Verification IP solution. Verification over many different configurations can be used with DisplayPort 2.1 and DisplayPort 1.4 designs, so you can choose the best version for your specific needs.
• The DisplayPort VIP provides a full-stack solution for Sink and Source devices with a comprehensive coverage model, protocol checkers, and an extensive test suite.
• More details are available on the DisplayPort Verification IP product page, Simulation VIP pages.
• If you have any queries, feel free to contact us at talk_to_vip_expert@cadence.com

Cadence PCIe/CXL VIP support for Partial Header Encryption in Integrity and Data Encryption.(read more)

The application of real-time data processing or responsiveness is crucial, such as in high-performance computing, data centers, or applications requiring low-latency data transfers. It enables efficient use of PCIe bandwidth and resources by intelligently managing memory write operations based on system dynamics and workload priorities. By effectively leveraging Deferrable Memory Write [DMWr], Devices can achieve optimized performance and responsiveness, aligning with the evolving demands of modern computing applications.

What Is Deferrable Memory Write?

Deferrable Memory Write (DMWr) ECN introduced this new memory transaction type, which was later officially incorporated in PCIe 5.0 to CXL2.0. This enhanced type of memory transaction is Deferrable Memory Write [DMWr], which flows as another type of existing Read/Write memory transaction; the major difference of this Deferrable Memory Write, where the Requester attempts to write to a given location in Memory Space using the non-posted DMWr TLP Type, it Postponing their completion of memory write transactions to improve overall system efficiency and performance, those memory write operation can be delay or deferred until other priority task complete.

The Deferrable Memory Write (DMWr) requires the Completer to return an acknowledgment to the Requester and provides a mechanism for the recipient to defer (temporarily refuse to service) the Request.

DMWr provides a mechanism for Endpoints and hosts to choose to carry out or defer incoming DMWr Requests. This mechanism can be used by Endpoints and Hosts to simplify the design of flow control, reduce latency, and improve throughput. The Deferrable Memory writes TLP format in Figure A.

(Fig A) Deferrable Memory writes TLP format.

Example Scenario

Here's how the DMWr works with a simplified example: Imagine a system with an endpoint device (Device A) and a host CPU (Device B). Device B wants to write data to Device A's memory, but due to varying reasons such as system bus congestion or prioritization of other transactions, Device A can defer the completion of the memory write request. Just follow these steps:

1. Initiation of Memory Write: Device B initiates a memory write transaction to Device A. This involves sending the memory write request along with the data payload over the PCIe physical layer link.
2. Acknowledgment and Deferral: Upon receiving the memory write request, Device A acknowledges the transaction but may decide to defer its completion. Device A sends an acknowledgment (ACK) back to Device B, indicating it has received the data and intends to complete the write operation but not immediately.
3. Deferred Completion: Device A defers the completion of the memory write operation to a later, more opportune time. This deferral allows Device A to prioritize other transactions or optimize the use of system resources, such as memory bandwidth or processor availability.
4. Completion and Response: At a later point, Device A completes the deferred memory write operation and sends a completion indication back to Device B. This completion typically includes any status updates or additional information related to the transaction.

Usage or Importance of DMWr

Deferrable Memory Write usage provides the improvement in the following aspects:

• Reduced Latency: By deferring less critical memory write operations, more critical transactions can be processed with lower latency, improving overall system responsiveness.
• Improved Efficiency: Optimizes the utilization of system resources such as memory bandwidth and CPU cycles, enhancing the efficiency of data transfers within the PCIe architecture.
• Enhanced Performance: Allows devices to manage and prioritize transactions dynamically, potentially increasing overall system throughput and reducing contention.

Challenges in the Implementation of DMWr Transactions

The implementation of deferrable memory writes (DMWr) introduces several advancements and challenges in terms of usage and verification:

1. Timing and Synchronization: DMWr allows transactions to be deferred, complicating timing requirements or completing them within acceptable timing windows to avoid protocol violations. Ensuring proper synchronization between devices becomes critical to prevent data loss or corruption.
2. Protocol Compliance: Verification must ensure compliance with ECN PCIe 6.0 and CXL specifications regarding when and how DMWr transactions can be initiated and completed.
3. Performance Optimization: While DMWr can improve overall system performance by reducing latency, verifying its impact on system performance and ensuring it meets expected benchmarks is crucial.
4. Error Handling: Handling errors related to deferred transactions adds complexity. Verifying error detection and recovery mechanisms under various scenarios (e.g., timeout during deferral) is essential.

Verification Challenges of DMWr Transactions

The challenges to verifying the DMWr transaction consist of all checks with respect to Function, Timing, Protocol compliance, improvement, Error scenario, and security usage on purpose, as well as Data integrity at the PCIe and CXL.

1. Functional Verification: Verifying the correct implementation of DMWr at both ends of the PCIe link (transmitter and receiver) to ensure proper functionality and adherence to specifications.
2. Timing Verification: Validating timing constraints associated with deferring writes and ensuring transactions are completed within specified windows without violating protocol rules.
3. Protocol Compliance Verification: Checking that DMWr transactions adhere to PCIe and CXL protocol rules, including ordering rules and any restrictions on deferral based on the transaction type.
4. Performance Verification: Assessing the impact of DMWr on overall system performance, including latency reduction and bandwidth utilization, through simulation and testing.
5. Error Scenario Verification: Creating and testing scenarios to verify error handling mechanisms related to DMWr, such as timeouts, retries, and recovery procedures.
6. Security Considerations: Assessing potential security vulnerabilities related to DMWr, such as data integrity risks during deferred transactions or exposure to timing-based attacks.

Major verification challenges and approaches are timing and synchronization verification in the context of implementing deferrable memory writes (DMWr), which is crucial due to the inherent complexities introduced by deferred transactions. Here are the key issues and approaches to address them:

Timing and Synchronization Issues

1. Transaction Completion Timing:
   • Issue: Ensuring deferred transactions are completed within the specified time window without violating protocol timing constraints.
   • Approach: Design an internal timer and checker to model worst-case scenarios where transactions are deferred and verify that they are complete within allowable latency limits. This involves simulating various traffic loads and conditions to assess timing under different scenarios.
2. Ordering and Dependencies:
   • Issue: Verifying that transactions deferred using DMWr maintain the correct ordering and dependencies relative to non-deferred transactions.
   • Approach: Implement test scenarios that include mixed traffic of DMWr and non-DMWr transactions. Verify through simulation or emulation that dependencies and ordering requirements are correctly maintained across the PCIe link.
3. Interrupt Handling and Response Times:
   • Issue: Verify the handling of interrupts and ensure timely responses from devices involved in DMWr transactions.
   • Approach: Implement test cases that simulate interrupt generation during DMWr transactions. Measure and verify the response times to interrupts to ensure they meet system latency requirements.

In conclusion, while deferrable memory writes in PCIe and CXL offer significant performance benefits, their implementation and verification present several challenges related to timing, protocol compliance, performance optimization, and error handling. Addressing these challenges requires rigorous testing and testbench of traffic, advanced verification methodologies, and a thorough understanding of PCIe specifications and also the motivation behind introducing this Deferrable Write is effectively used in the CXL further. Outcomes of Deferrable Memory Write verify that the performance benefits of DMWr (reduced latency, improved throughput) are achieved without compromising timing integrity or violating protocol specifications.

In summary, PCIe and CXL are complex protocols with many verification challenges. You must understand many new Spec changes and consider the robust verification plan for the new features and backward compatible tests impacted by new features. Cadence's PCIe 6.0 Verification IP is fully compliant with the latest PCIe Express 6.0 specifications and provides an effective and efficient way to verify the components interfacing with the PCIe 6.0 interface. Cadence VIP for PCIe 6.0 provides exhaustive verification of PCIe-based IP and SoCs, and we are working with Early Adopter customers to speed up every verification stage.

More Information

• For more info on how Cadence PCIe Verification IP and TripleCheck VIP enable users to confidently verify PCIe 6.0, see our VIP for PCI Express, VIP for Compute Express Link, and TripleCheck for PCI Express
• See the PCI-SIG website for more details on PCIe in general and the different PCI standards.

The Sigrity and Systems Analysis (SIGRITY/SYSANLS) 2024.1 release is now available for download at Cadence Downloads . For the list of CCRs fixed in this release, see the README.txt file in the installation hierarchy. SIGRITY/SYSANLS 2024.1 Here is a list of some of the key updates in the SIGRITY/SYSANLS 2024.1 release: For more details about these and all the other new and enhanced features introduced in this release , refer to the following document: Sigrity Release Overview and Common Tools What's New . Supported Platforms and Operating Systems Platform and Architecture X86_64 (lnx86) Windows (64 bit) Development OS RHEL 8.4 Windows Server 2022 Supported OS RHEL 8.4 and above RHEL 9 SLES 15 (SP3 and above) Windows 10 Windows 11 Windows Server 2019 Windows Server 2022 Systems Analysis 2024.1 Clarity 3D Solver Clarity 3D Layout Structure Optimization Workflow : A new workflow, Clarity 3D Layout Structure Optimization Workflow, has been added to Clarity 3D Layout. This workflow integrates Allegro PCB Designer with Clarity 3D Layout for high-speed structure optimization. Component Geometry Model Editor : The new Clarity 3D Layout editor lets you set up ports, solder bumps/balls/extrusions, and two-terminal and multi-terminal circuits using a single GUI. Coaxial Open Port Option Added to Port Setup Wizard : The Coaxial Open Port option lets you create ports for each target net pin and reference net pin in Clarity 3D Layout. The nearby reference net pins are then used as a reference for each target net pin, reducing the number of ports needed. In addition, the ports of unused reference net pins are shorted to the ground. Parametric Import Option Added : Two new options, Parametric Import and Default Import , have been added to the Tools – Launch Clarity3DWorkbench menu. The Parametric Import option lets you import the design along with its parameters into Clarity 3D Workbench. The Default Import option lets you ignore the parameters when importing the design into Clarity 3D Workbench. Component Library Added to Generate 3D Components : Clarity 3D Workbench now includes a new component library that lets you use predefined 3D component templates or add existing 3D components to create 3D designs and simulation models. AI-Powered Content Search Capability : Clarity 3D Workbench and Clarity 3D Transient Solver now support an AI-powered capability for searching the content and displaying relevant information. Expression Parser to Handle Undefined Parameters : Clarity 3D Workbench and Clarity 3D Transient Solver support writing expressions or equations containing undefined parameters in the Property window to describe a simulation variable. The improved expression parser automatically detects any undefined parameter in an expression and prompts users to specify their values. This capability lets you define a model or a simulation variable as a function instead of specifying static values. For detailed information, refer to Clarity 3D Layout User Guide and Clarity 3D Workbench User Guide on the Cadence Support portal. Clarity 3D Transient Solver Mesh Processing Improved to Simulate Large Use Cases : Clarity 3D Transient Solver leverages a new meshing algorithm that enhances overall mesh processing, specifically for large designs and use cases. The new algorithm dramatically improves the mesh quality, minimum mesh size, number of mesh key points, total mesh number, and memory usage. Advanced Material Processing Engine : The material processing capability has been enhanced to handle thin outer metal, which previously resulted in open and short issues in some designs. In addition, the material processing engine offers improved mode extraction for particular use cases, including waveguide and coaxial designs. Characteristic Impedance Calculation Improved : The solver engine now uses a new analytical calculation method to calculate the characteristic impedance of coaxial designs with improved accuracy. For detailed information, refer to Clarity 3D Transient Solver User Guide on the Cadence Support portal. Celsius Studio Celsius Interchange Model Introduced : Celsius Studio now supports Celsius Interchange Model generation, which is a 3D model derived from detailed physical designs for multi-physics and multi-scale analysis. This Celsius Interchange Model file ( .cim ) serves as a design information carrier across Celsius Studio tools, enabling a variety of simulation and analysis tasks . Celsius 3DIC Thermal Workflow Improvements : The Thermal Simulation workflows in Celsius 3DIC have been significantly enhanced. Key improvements include: Advanced Power Setup with Transient Power Function and Multi Mode options Enhanced GUI for the Mesh Control and Simulation Control tabs Improved meshing capabilities Celsius Interchange Model ( .cim ) generation Material library support for block and connections Import of Heat Transfer Coefficients (HTCs) from a CFD file Bump creation through the Bump Array Wizard Layer Stackup CSV file generation Celsius 3DIC Warpage and Stress Workflow Enhancements : The Warpage and Stress workflow in Celsius 3DIC has undergone significant improvements, such as: Improved multi-stage warpage simulation flow for 3DIC packaging process Enhanced GUI for the Mesh Control , Simulation Control , and Stress Boundary Conditions tabs Support for large deformations and temperature profiles Bump creation through the Bump Array Wizard New constraint types Enhanced meshing capabilities Geometric Nonlinearity Support in Warpage and Stress Analysis : Large deformation analysis is now supported in warpage and stress studies. This study uses the Total Lagrangian approach to model geometric nonlinearities in simulation, which allows accurate prediction of final deformations. Thermal Network Extraction and Simulation : In the solid extraction flow in Celsius 3D Workbench, you can now import area-based power map files to create terminals. For designs with multiple blocks, this capability allows automatic terminal creation, eliminating the need to manually create and set up 2D sheets individually. Additionally, thermal throttling feature is now supported in Celsius Thermal Network. This makes it ideal for preliminary analyses or when a quick estimation is required. It runs significantly faster than 3D models, allowing for quicker iterations and more efficient decision-making. For detailed information, refer to the Celsius 3DIC User Guide , Celsius Layout User Guide and Celsius 3D Workbench User Guide on the Cadence Support portal. Sigrity 2024.1 Layout Workbench Improved Graphical User Interface : A new option, Use Improved User Interface , has been added in the Themes page of the Options dialog box in the Layout Workbench GUI. In the new GUI, the toolbar icons and menu options have been enhanced and rearranged. For detailed information, refer to Layout Workbench User Guide on the Cadence Support portal. Broadband SPICE Python Script Integration with Command Line for Simulation Tasks : Broadband SPICE lets you run Python scripts directly from the command line for performing simulation and analysis. The new -py and *.py options make it easier to integrate Python scripts with the command-line operations. This update streamlines the process of automating and customizing simulations from the command line, which makes your simulation tasks faster and easier. For detailed information, refer to Broadband SPICE User Guide on the Cadence Support portal. Celsius PowerDC Block Power Assignment (BPA) File Format Support : PowerDC now supports the BPA file format. Similar to the Pin Location (PLOC) file, the BPA file is a current assignment file that defines the total current of a power grid cell, which is then equally distributed across the power pins within the cell. This provides better control over the power distribution. Ability to Run Multiple IR Drop Cases Sequentially : You can now select multiple result sinks from the Current-Limited IR Drop flow and run IR Drop analysis for them sequentially. PowerDC automatically runs the simulations in sequence after you select multiple result sinks. This saves time by automating the process. Enhanced Support for Mixed Conversion Devices : PowerDC now supports mixing different conversion devices, such as switching regulators and linear regulators within a single DC-DC/LDO instance. This enhancement offers added flexibility by letting you configure each instance in your design according to your specific needs. For detailed information, refer to PowerDC User Guide on the Cadence Support portal. PowerSI Monte Carlo Method Added : A new option, Monte Carlo Method, has been added in the Optimality dialog box. This option lets you create multiple random samples to depict variations in the input parameters and assess the output. Channel Check Optimization Added : The S-Parameter Assessment workflow in PowerSI now supports Channel Check Optimization . It uses the AI-driven Multidisciplinary Analysis and Optimization (MDAO) technology that lets you optimize your design quickly and efficiently with no accuracy loss. For detailed information, refer to PowerSI User Guide on the Cadence Support portal. SPEEDEM Multi-threaded Matrix Solver Support Added : The Enable Multi-threaded Matrix Solver check box has been added that lets you accelerate the simulation speed for high-performance computing. This check box provides two options, Automatic and Always, to include the -lhpc4 or -lhpc5 parameter, respectively, in the SPEEDEM Simulator (SPDSIM) before running the simulation. For detailed information, refer to the SPEEDEM User Guide on the Cadence Support portal. XtractIM Options to Skip or Calculate Special DC-R Simulation Results : The Skip DC_R of Each Path and Only DC_R of Each Path options have been added to the Setup menu. Skip DC_R of Each Path : This option lets you skip the calculation of the DC-R result during the simulation. Other results, such as SPICE T-model , RL_C of Each Path , Coupling of Each Path , etc., are still calculated. Only DC_R of Each Path : This option lets you calculate the DC-R result only during the simulation. Other results, such as SPICE T-model , RL_C of Each Path , Coupling of Each Path , etc., are not calculated. Color Assignment for Pin Matching : The MCP Auto Connection window includes the Display Color Editor , which lets you assign a color for pin matching. It helps you easily identify the matching pins in the left and right sections of the MCP Auto Connection window . Ability to Save Simulations Individually : The Save each simulation individually check box has been added to the Tools - Options - Edit Options - Simulation (Basic) - General form. Select this check box and run the simulation to generate a simulation results folder containing files and logs with a timestamp for each simulation. Reuse of SPD File Settings : The XtractIM setup check box lets you import an existing package setup to reuse the configurations and settings from one .spd file to another. For detailed information, refer to XtractIM User Guide on the Cadence Support portal. Documentation Enhancements Cloud-Based Help System Upgraded The cloud-based help system, Doc Assistant, has been upgraded to version 24.10, which contains several new features and enhancements over the previous 2.03 version. Sigrity Release Team Please send your questions and feedback to sigrity_rmt@cadence.com .

This November, the engineering and simulation community is set to converge in China for an event that promises to be nothing short of revolutionary. The 2024 BETA CAE Systems China Open Meeting, taking place in the vibrant cities of Beijing and Shanghai on November 5 and 7 , respectively, is a must-attend for anyone looking to stay at the forefront of technological innovation in simulation solutions. Prepare to be inspired by Ben Gu , the visionary Corporate VP of Research and Development at Cadence. He will lead both meetings in Beijing and Shanghai with his keynote on " A New Millennium in Multiphysics System Analysis ." This thought-provoking keynote is expected to provide attendees with a glimpse into the future of engineering simulation and analysis. What sets the BETA CAE Systems Open Meetings apart is not just the high caliber of speakers but also the hands-on training sessions designed to enhance your technical expertise with the BETA CAE software suite. Whether you are an inexperienced individual seeking to acquire fundamental knowledge or an accomplished professional endeavoring to hone your expertise, these training sessions following the open meetings are meticulously tailored to meet your needs. Join Us at the BETA CAE Systems Open Meeting in Beijing The BETA CAE Systems Open Meeting in Beijing will feature a keynote speech by Peng Qiao , Senior Engineer at Great Wall Motors Co., Ltd, on Multidisciplinary Optimization Techniques for Automotive Control Arms . ( View detailed agenda for Beijing. ) When: November 5, 2024 Where: Grand Metropark Hotel Beijing If this sounds interesting, register today for the BETA CAE Systems Beijing Open Meeting by clicking the button below. Don't Miss Out on the BETA CAE Systems Open Meeting in Shanghai After the BETA CAE Systems Open Meeting in Beijing, the next meeting in China will be in Shanghai. During this event, Liu Deping, CAE Engineer from Zhejiang Geely Automobile Research Institute Co., Ltd, will deliver a keynote speech on the Application of ANSA in the Simulation Development Cycle . ( View detailed agenda for Shanghai. ) When: November 7, 2024 Where: InterContinental Shanghai Jing'an Following the open meeting on November 7 will be an exclusive training day on November 8. This session will provide attendees with practical experience using the BETA CAE software to improve their technical skills and provide hands-on knowledge of the software. If you find this intriguing, register now for the BETA CAE Systems Shanghai Open Meeting by clicking the button below. Why Attend? Gain firsthand insights into the latest developments in simulation technology Learn from real-world applications and success stories from various industries Connect and exchange ideas with experts in a collaborative environment Mark your calendars for this unparalleled opportunity to explore the forefront of simulation technology. Whether you're aiming to broaden your knowledge, enhance your technical skills, or connect with industry leaders, the BETA CAE Systems Open Meetings are your gateway to the future of engineering. Join us and be part of shaping the next wave of innovation in the simulation world.

Allegro X System Capture offers a complete ecosystem for library development. This post introduces the latest DE-HDL Library Development using System Capture course in which you learn how to create different library objects. As a librarian, you often work with numerous libraries. Your tasks include creating or modifying symbols for libraries. To use Allegro X System Capture to create a library, you can follow the steps in the following flowchart: Let’s go through each step in detail. Setting the CDS_SITE Variable Before you start library development for a new project, set the CDS_SITE system environment variable. This step is required to access libraries and other configuration files. Creating a Project in Allegro X System Capture The next step is to create a project in Allegro X System Capture. Adding a Library to the Project Symbol development consists of creating symbol graphics, electrical data, and properties used by different tools in the PCB design flow. To add a library to a project, first create a library in the Libraries pane of the Project e xplorer. Creating Library Symbols The library development process supports the creation of various types of symbols. Creating a Symbol with Multiple Views You can generate multiple views of the same symbol using the Duplicate command. For example, a discrete symbol, such as a resistor, can have multiple views, as shown in the following image: Creating a Split Symbol For advanced designs, you often need to create library symbols and break them into multiple sections to support the design process. When a symbol shows all the logical pins in the physical package, it is called a single-section or flat symbol. Many large ICs have several pins and the symbols need to fit on a single schematic page. One workaround is to use vector pin names on a symbol to reduce its size, although manufacturers prefer schematics that show each pin. You can divide these high-pin count devices into smaller pieces, where each piece is a separate version of the part. Such parts are referred to as split parts or multi-section symbols. For multi-section symbols, you can create two types of split parts—symmetrical and asymmetrical. Symmetrical Split Symbols A symmetrical split symbol has only one symbol graphic, which holds two or more identical logic symbols, each with its own unique physical pin numbers. You can create a symmetrical split symbol using the Duplicate Section icon in the canvas window. Each symbol section contains the same set of pins but different pin numbers, as shown in the following image: Asymmetrical Split Symbols An asymmetrical split symbol is a symbol whose physical package contains one or more unique schematic symbols. You can create an asymmetrical split symbol by clicking the New Section icon in the canvas window. Asymmetrical symbols have a unique set of logical pins, as shown in the following image: Creating Symbols Using the Spreadsheet Interface To simplify the development of large symbols, Allegro X System Capture has a Spreadsheet Interface . You can copy from a spreadsheet into the interface. This saves time and helps minimize errors introduced by manual entry. In conclusion, the DE-HDL library development using Allegro X System Capture course involves several critical steps and supports various symbol creation techniques. This course helps librarians create and modify symbols effortlessly and deepens their understanding of library development within Allegro X System Capture. To learn more about this topic, enroll in the DE-HDL Library Development using Allegro X System Capture course on the Cadence Support portal . Click the training byte link now or visit Cadence Support and search for training bytes under Video Library. If you find the post useful and want to delve deeper into training details, enroll in the following online training course for lab instructions and a downloadable design: DE-HDL Library Development using Allegro X System Capture (Online). You can become Cadence Certified once you complete the course. Cadence Training Services now offers free Digital Badges for all popular online training courses. 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 add the digital badge to your email signature or any social media channels, such as Facebook or LinkedIn, to highlight your expertise. To find out more, see the blog post Take a Cadence Masterclass and Get a Badge . You might also be interested in the training Learning Map that guides you through recommended course flows as well as tool experience and knowledge-level training modules. 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As a verification engineer, you’re surely looking for ways to automate the debugging process. Have you developed your own scripts to ease specific debugging steps that tools don’t offer? Working with scripts locally and manually is challenging—so is reusing and organizing them. What if there was a way to create your own app with the required functionality and register it with the tool? The answer to that question is “Yes!” The Verisium Debug Python App Store lets you instantly add additional features and capabilities to your Verisium Debug Application using Python Apps that interact with Verisium Debug via the Python API. Join me, Principal Education Application Engineer Bhairava Prasad, for this Training Webinar and discover the Verisium Debug Python App Store. The app store allows you to search for existing apps, learn about them, install or uninstall them, and even customize existing apps. Date and Time Wednesday, November 20, 2024 07:00 PST San Jose / 10:00 EST New York / 15:00 GMT London / 16:00 CET Munich / 17:00 IST Jerusalem / 20:30 IST Bangalore / 23:00 CST Beijing REGISTER To register for this webinar, sign in with your Cadence Support account (email ID and password) to log in to the Learning and Support System*. Then select Enroll to register for the session. Once registered, you’ll receive a confirmation email containing all login details. A quick reminder: If you haven’t received a registration confirmation within one hour of registering, please check your spam folder and ensure your pop-up blockers are off and cookies are enabled. For issues with registration or other inquiries, reach out to eur_training_webinars@cadence.com . Like this topic? Take this opportunity and register for the free online course related to this webinar topic: Verisium Debug Training To view our complete training offerings, visit the Cadence Training website Want to share this and other great Cadence learning opportunities with someone else? Tell them to subscribe . Hungry for Training? Choose the Cadence Training Menu that’s right for you. Related Courses Xcelium Simulator Training Course | Cadence Related Blogs Unveiling the Capabilities of Verisium Manager for Optimized Operations - Verification - Cadence Blogs - Cadence Community Verisium SimAI: SoC Verification with Unprecedented Coverage Maximization - Corporate News - Cadence Blogs - Cadence Community Verisium SimAI: Maximizing Coverage, Minimizing Bugs, Unlocking Peak Throughput - Verification - Cadence Blogs - Cadence Community Related Training Bytes Introducing Verisium Debug (Video) (cadence.com) Introduction to UVM Debug of Verisium Debug (Video) (cadence.com) Verisium Debug Customized Apps with Python API Please see course learning maps a visual representation of courses and course relationships. Regional course catalogs may be viewed here . *If you don’t have a Cadence Support account, go to Cadence User Registration and complete the requested information. Or visit Registration Help .

This year, the Cadence Giving Foundation (CGF) launched Fem.AI to achieve a more inclusive tech sector, and the inaugural Fem.AI Summit that took place on October 1 was a luminary in a world where technology is evolving at an unprecedented pace. The summit not only excelled in its mission to enlighten, empower, and mobilize stakeholders across various industries on the issue of gender disparity in high tech and AI, but was a celebration of innovation, diversity, and empowerment. As we reflect on the moments that made the summit unforgettable, it's clear that the event was more than just a meeting of minds—it was a movement for change! Shaping Tomorrow Together Cadence’s president and CEO, Anirudh Devgan, stated, “Women’s talent and perspectives are crucial to shaping the future of AI.” Devgan’s words epitomized the driving force behind the first-ever Fem.AI Summit which brought together innovators, educators, business leadership, and investors across industries to create an ecosystem that ensures women can fully participate in the AI revolution and burgeoning AI economy. The energy of pioneers ready to collectively disrupt the status quo filled the air, and as the day-long summit began, it became clear that we were part of something truly groundbreaking. The event's lineup of speakers held discussions that went beyond the technical aspects of AI, emphasizing the vital importance of diversity in technology. Such insights were lent by leading voices from MIT, Stanford, and UC Berkeley, who set the stage for inspiring discussions with speakers like Dr. Joy Buolamwini, Founder of the Algorithmic Justice League, and Reshma Saujani, Founder and CEO of Moms First and Girls Who Code. Included in this lineup of leading figures was Dr. Chelsea Clinton, Vice Chair of the Clinton Foundation, who left us with her hopes for the future of women in AI: “I’m hoping because of company-wide commitments like what we’re experiencing here today thanks to Cadence, that the people who will be part of designing [future technologies] will have a different group of people around the proverbial table or the computer screens doing that… and that women will be more integral into the conceptualization and then the actualization of AI-driven enterprises.” The hopes and visions for women in AI cannot manifest in a vacuum, they must be achieved with the support of individuals and systems from education all the way to the upper echelons of leadership. It is with this understanding, that Fem.AI is committed to investing in women at every stage of their STEM journey. Breaking Barriers It is with this ideal that we were honored to hear from women breaking through barriers of gender, race, and class in achieving pinnacles of success in areas of science and technology. Dr. Sarah H. Chen, Postdoctoral Researcher at Stanford and Thriving Stars Scholar at MIT, Niki Karanikola, Machine Learning Engineer and Break Through Tech AI Scholar at MIT, and Katya Echazarreta, NASA’s first Mexican Astronaut, showcased the resilience and determination that drive progress within and beyond our industry. Through their stories of persevering despite all odds, we were reminded that supporting students in STEM can create generational change with impacts beyond the realms of AI and technology. The final speaker at the Cadence Fem.AI Summit, the trailblazing Brandi Chastain, Founder of Bay FC, World Cup Champion, and Olympic Gold Medalist, left us with a powerful reminder that when faced with this opportunity: “Our purpose needs to be intentional” especially in building the future of technology and AI where “diversity is not something to be afraid of, but something to be embraced.” Echoing this sentiment, summit attendees left the event reminded of the crucial role we collectively play in ensuring women are part of this tech revolution. Moving Forward While the summit may have concluded, its impact will continue through individuals, companies, and communities aspiring to achieve an equitable tech sector. This is just the start, and we must take collective action now. We hope that you will join Cadence to ensure that we clear the path and catalyze women's role in the AI revolution! Meet Our Partners Our partners are making Fem.AI’s vision a reality through their important work advancing women in technology, including fostering STEM excellence in higher education, launching STEM careers, and achieving gender diversity in leadership. Learn more about the important work of each of our partners by visiting their pages: Break Through Tech Last Mile Education Fund Fast Forward Generation VC Include Global Semiconductor Alliance Join the Fem.AI Alliance Joining the Fem.AI Alliance signals that your company or institution is committed to evolving the AI workforce. By increasing the representation of women in AI, we aim to broaden the talent pool and the perspective so that AI represents us all. Through the Fem.AI Alliance, companies and institutions can share best practices, guidance, and inspiration. Since its launch, companies like the Equinix Foundation, NetApp, NVIDIA, Unity Technologies, and Workday have joined the Alliance in their commitment to Fem.AI’s work and mission. Visit Fem.AI to get involved today or contact Fem.AI@cadence.com .

DDR5 DIMM Architectures The DDR5 generation of Double Data Rate DRAM memories has experienced rapid adoption in recent years. In particular, the JEDEC-defined DDR5 Dual Inline Memory Module (DIMM) cards have become a mainstay for systems looking for high-density, high-bandwidth, off-chip random access memory[1]. Within a short time, the DIMM architecture evolved from an interconnected hierarchy of only SDRAM memory devices (UDIMM[2]) to complex subsystems of interconnected components (RDIMM/LRDIMM/MRDIMM[3]). DIMM Designs and Popular Verification Use Cases The growing complexity of the DIMMs presented a challenge for pre-silicon verification engineers who could no longer simply validate against single DDR5 SDRAM memory models. They needed to consider how their designs would perform against DIMMs connected to each channel and operating at gigahertz clock speeds. To address this verification gap, Cadence developed DDR5 DIMM Memory Models that encapsulated all of the architectural complexities presented by real-world DIMMs based on a robust, easy-to-use, easy-to-debug, and easy-to-reconfigure methodology. This memory-subsystem-in-a-single-instance model has seen explosive adoption among the traditional IP Developer and SOC Integrator customers of Cadence Memory Models. The Cadence DIMM models act as a single unit with all of the relevant DIMM components instantiated and interconnected within, and with all AC/Timing parameters among the various components fully matched out-of-the-box, based on JEDEC specifications as well as datasheets of actual devices in the market. The typical use-case for the DIMM models has been where the DUT is a DDR5 Memory Controller + PHY IP stack, and the validation plan mandated compliance with the JEDEC standards and Memory Device vendor datasheets. Unique Use Case for the DIMM Discrete Component Models Although the Cadence DIMM models have enjoyed tremendous proliferation because of their cohesive implementation and unified user API, the actual DIMM Models are built on top of powerful, flexible discrete component models, each of which was designed to stand on its own as a complete SystemVerilog UVM-based VIP. All of these discrete component models exist in the Cadence VIP Catalog as standalone VIPs, complete with their own protocol compliance checking capabilities and their own configuration mappings comprehensively modeling individual AC/Timing parameters. Because of this deliberate design decision, the Cadence DIMM Discrete Component Models can support a unique use-case scenario. Some users seek to develop IC Designs for the various DIMM components. Such users need verification environments that can model the individual components of a DIMM and allow them the option to replace one or another component with their Component Design IP. They can then validate that their component design is fully compatible with the rest of the components on the DIMM and meets the integrity of the overall DIMM compliance with JEDEC standards or Memory Vendor datasheets. The Cadence Memory VIP portfolio today includes various examples that demonstrate how customers can create DIMM “wrappers” by selecting from among the available DIMM discrete component models and “stitching” them together to build their own custom testbench around their specific Component Design IP. A Solution for Unique Component Scenarios The Cadence DDR5 DIMM Memory Models and DIMM Discrete Component Models can provide users with a flexible approach to validating their specific component designs with a fully populated pre-silicon environment. Augmented Verification Capabilities When the DIMM “wrapper” model is augmented with the Cadence DFI VIP[4] that can simulate an MC+PHY stack and offers a SystemVerilog UVM test API to the verification engineer, the overall testbench transforms into a formidable pre-silicon validation vehicle. The DFI VIP is designed as a combination of an independent DFI MC VIP and a DFI PHY VIP connected to each other via the DFI Standard Interface and capable of operating seamlessly as a single unit. It presents a UVM Sequence API to the user into the DFI MC VIP with the Memory Interface of the PHY VIP connected to the DIMM “wrapper” model. With this testbench in hand, the user can then fully take advantage of the UVM Sequence Library that comes with the DFI VIP to enable deep validation of their Component Design inside the DIMM “wrapper” model. Verification Capabilities Further Enhanced A possible further enhancement comes with the potential addition of an instance of the Cadence DIMM Memory Model in a Passive Monitor mode at the DRAM Memory Interface. The DIMM Passive Monitor consumes the same configuration describing the DIMM “wrapper” in the testbench, and thus can act as a reference model for the DIMM wrapper. If the DIMM Passive Monitor responds successfully to accesses from the DFI VIP, but the DIMM wrapper does not, then it exposes potential bugs in the DUT Components or in the settings of their AC/Timing parameters inside the DIMM wrapper. Debuggability, Interface Visibility, and Protocol Compliance One of the key benefits of the DIMM Discrete Component Models that become manifest, whether in terms of the unique use-case scenario described here, or when working with the wholly unified DDR5 DIMM Memory Models, is the increased debuggability of the protocol functionality. The intentional separation of the discrete components of a DIMM allows the user to have full visibility of the memory traffic at every datapath landmark within a DIMM structure. For example, in modeling an LRDIMM or MRDIMM, the interface between the RCD component and the SDRAM components, the interface between the RCD component and the DB components, and the interface between the SDRAM components and the DB components—all are visible and accessible to the user. The user has full access to dump the values and states of the wire interconnects at these interfaces to the waveform viewer and thus can observe and correlate the activity against any protocol violations flagged in the trace logs by any one or more of the DIMM Discrete Component Models. Access to these interfaces is freely available when using the DIMM Discrete Component Models. On the unified DDR5 DIMM Memory Models, a feature called Debug Ports enables the same level of visibility into the individual interconnects amidst the SDRAM components, RCD components, and DB components. When combined with the Waveform Debugger[5] capability that comes built-in with the VIPs and Memory Models offered by Cadence and used with the Cadence Verisium Debug[6] tool, the enhanced debuggability becomes a powerful platform. With these debug accesses enabled, the user can pull out transaction streams, chip state and bank state streams, mode register streams, and error message streams all right next to their RTL signals in the same Verisium Debug waveform viewer window to debug failures all in one place. The Verisium Debug tool also parses all of the log files to probe and extract messages into a fully integrated Smart Log in a tabbed window fully hyperlinked to the waveform viewer, all at your fingertips. A Solution for Every Scenario Cadence's DDR5 DIMM Memory Models and DIMM Discrete Component Models , partnered with the Cadence DFI VIP, can provide users with a robust and flexible approach to validating their designs thoroughly and effectively in pre-silicon verification environments ahead of tapeout commitments. The solution offers unparalleled latitude in debuggability when the Debug Ports and Waveform Debugger functions of the Memory Models are switched on and boosted with the use of the Cadence Verisium Debug tool. [1] Shyam Sharma, DDR5 DIMM Design and Verification Considerations , 13 Jan 2023. [2] Shyam Sharma, DDR5 UDIMM Evolution to Clock Buffered DIMMs (CUDIMM) , 23 Sep 2024. [3] Kos Gitchev, DDR5 12.8Gbps MRDIMM IP: Powering the Future of AI, HPC, and Data Centers , 26 Aug 2024. [4] Chetan Shingala and Salehabibi Shaikh, How to Verify JEDEC DRAM Memory Controller, PHY, or Memory Device? , 29 Mar 2022. [5] Rahul Jha, Cadence Memory Models - The Gold Standard , 15 Apr 2024. [6] Manisha Pradhan, Accelerate Design Debugging Using Verisium Debug , 11 Jul 2023.

On November 5, 2024, the Cadence Bangalore Toastmasters Club celebrated a significant milestone by hosting its 50th meeting. Established in December 2020, the club was created to provide a supportive environment for individuals looking to improve their communication and leadership skills. Over the years, the club has evolved into a vibrant community filled with success stories of personal development and newfound confidence. A testament to the club's dedication is its achievement of the "Select Distinguished Club" status during the 2023-2024 program year. By fulfilling 7 out of 10 distinguished goals, the club highlighted its commitment to excellence—a success driven by its vibrant members' relentless focus and perseverance. The strategic insight gained from regular Toastmasters committee meetings and the influential "Moments of Truth" sessions held in 2023 and 2024 are key to this success. Our club members have consistently demonstrated strong performance in various speech contests, with notable achievements across multiple levels. In 2023, members excelled in Evaluation and Table Topics contests, reaching the district level while advancing to the Division Level in the International Speech Contest. Continuing their success into 2024, members again qualified for area-level contests, securing third-place positions in the Evaluation and Table Topics categories, highlighting the club's dedication and competitive spirit. The 50th meeting was based on the theme of serendipity. It was not only a milestone celebration but also a vibrant festival of achievements and growth. The day buzzed with energy as activities like a spirited Treasure Hunt injected enthusiasm and camaraderie among attendees. Distinguished guests, including Kripa Venkitachalam and Madhavi Rao, enriched the occasion with inspiring speeches. Madhavi reignited the club's spirit, while Kripa's discourse on the Growth Mindset and the "Power of Yet" encouraged members to pursue continuous self-improvement. The Cadence Bangalore Toastmasters Club is enthusiastic about its promising future and is committed to creating an environment that promotes personal and professional growth. Many members are close to completing their Toastmasters levels and pathways, and this term, a new group of approximately 30 individuals has joined, bringing the total membership to 52. This vibrant community is just beginning its journey and is eager to reach new milestones together through mutual support and a shared commitment to excellence. The transformations experienced by many club members are truly compelling. They often share how the club has significantly improved their communication skills and boosted their confidence. One member recalls, "Before joining, I found public speaking intimidating. Now, I embrace every opportunity to share my ideas." Another member highlights how the club's supportive environment helped him overcome his fear of public speaking, propelling his career to new heights. This culture of constructive feedback and continuous improvement has inspired countless members to pursue their dreams with renewed determination and optimism. The Cadence Bangalore Toastmasters Club's journey is a living testament to the power of community and the potential within each of us to grow and achieve greatness. As the club continues to evolve and inspire, it serves as a beacon for those aspiring to transform their skills and seize their moment in the spotlight. Learn more about life at Cadence.

Peripheral Component Interconnect Express (PCIe) is a high-speed interface standard widely used for connecting processors, memory, and peripherals. With the increasing reliance on PCIe to handle sensitive data and critical high-speed data transfer, ensuring data integrity and encryption during verification is the most essential goal. As we know, in the field of verification, randomization is a key technique that drives robust PCIe verification. It introduces unpredictability to simulate real-world conditions and uncover hidden bugs from the design. This blog examines the significance of randomization in PCIe IDE verification, focusing on how it ensures data integrity and encryption reliability, while also highlighting the unique challenges it presents. For more relevant details and understanding on PCIe IDE you can refer to Introducing PCIe's Integrity and Data Encryption Feature . The Importance of Data Integrity and Data Encryption in PCIe Devices Data Integrity : Ensures that the transmitted data arrives unchanged from source to destination. Even minor corruption in data packets can compromise system reliability, making integrity a critical aspect of PCIe verification. Data Encryption : Protects sensitive data from unauthorized access during transmission. Encryption in PCIe follows a standard to secure information while operating at high speeds. Maintaining both data integrity and data encryption at PCIe’s high-speed data transfer rate of 64GT/s in PCIe 6.0 and 128GT/s in PCIe 7.0 is essential for all end point devices. However, validating these mechanisms requires comprehensive testing and verification methodologies, which is where randomization plays a very crucial role. You can refer to Why IDE Security Technology for PCIe and CXL? for more details on this. Randomization in PCIe Verification Randomization refers to the generation of test scenarios with unpredictable inputs and conditions to expose corner cases. In PCIe verification, this technique helps us to ensure that all possible behaviors are tested, including rare or unexpected situations that could cause data corruption or encryption failures that may cause serious hindrances later. So, for PCIe IDE verification, we are considering the randomization that helps us verify behavior more efficiently. Randomization for Data Integrity Verification Here are some approaches of randomized verifications that mimic real-world traffic conditions, uncovering subtle integrity issues that might not surface in normal verification methods. 1. Randomized Packet Injection: This technique randomized data packets and injected into the communication stream between devices. Here we Inject random, malformed, or out-of-sequence packets into the PCIe link and mix valid and invalid IDE-encrypted packets to check the system’s ability to detect and reject unauthorized or invalid packets. Checking if encryption/decryption occurs correctly across packets. On verifying, we check if the system logs proper errors or alerts when encountering invalid packets. It ensures coverage of different data paths and robust protocol check. This technique helps assess the resilience of the IDE feature in PCIe in below terms: (i) Data corruption: Detecting if the system can maintain data integrity. (ii) Encryption failures: Testing the robustness of the encryption under random data injection. (iii) Packet ordering errors: Ensuring reordering does not affect data delivery. 2. Random Errors and Fault Injection: It involves simulating random bit flips, PCRC errors, or protocol violations to help validate the robustness of error detection and correction mechanisms of PCIe. These techniques help assess how well the PCIe IDE implementation: (i) Detects and responds to unexpected errors. (ii) Maintains secure communication under stress. (iii) Follows the PCIe error recovery and reporting mechanisms (AER – Advanced Error Reporting). (iv) Ensures encryption and decryption states stay synchronized across endpoints. 3. Traffic Pattern Randomization: Randomizing the sequence, size, and timing of data packets helps test how the device maintains data integrity under heavy, unpredictable traffic loads. Randomization for Data Encryption Verification Encryption adds complexity to verification, as encrypted data streams are not readable for traditional checks. Randomization becomes essential to test how encryption behaves under different scenarios. Randomization in data encryption verification ensures that vulnerabilities, such as key reuse or predictable patterns, are identified and mitigated. 1. Random Encryption Keys and Payloads: Randomly varying keys and payloads help validate the correctness of encryption without hardcoding assumptions. This ensures that encryption logic behaves correctly across all possible inputs. 2. Randomized Initialization Vectors (IVs): Many encryption protocols require a unique IV for each transaction. Randomized IVs ensure that encryption does not repeat patterns. To understand the IDE Key management flow, we can follow the below diagram that illustrates a detailed example key programming flow using the IDE_KM protocol. Figure 1: IDE_KM Example As Figure 1 shows, the functionality of the IDE_KM protocol involves Start of IDE_KM Session, Device Capability Discovery, Key Request from the Host, Key Programming to PCIe Device, and Key Acknowledgment. First, the Host starts the IDE_KM session by detecting the presence of the PCIe devices; if the device supports the IDE protocol, the system continues with the key programming process. Then a query occurs to discover the device’s encryption capabilities; it ensures whether the device supports dynamic key updates or static keys. Then the host sends a request to the Key Management Entity to obtain a key suitable for the devices. Once the key is obtained, the host programs the key into the IDE Controller on the PCIe endpoint. Both the host and the device now share the same key to encrypt and authenticate traffic. The device acknowledges that it has received and successfully installed the encryption key and the acknowledgment message is sent back to the host. Once both the host and the PCIe endpoint are configured with the key, a secure communication channel is established. From this point, all data transmitted over the PCIe link is encrypted to maintain confidentiality and integrity. IDE_KM plays a crucial role in distributing keys in a secure manner and maintaining encryption and integrity for PCIe transactions. This key programming flow ensures that a secure communication channel is established between the host and the PCIe device. Hence, the Randomized key approach ensures that the encryption does not repeat patterns. 3. Randomization PHE: Partial Header Encryption (PHE) is an additional mechanism added to Integrity and Data Encryption (IDE) in PCIe 6.0. PHE validation using a variety of traffic; incorporating randomization in APIs provided for validating PHE feature can add more robust Encryption to the data. Partial Header Encryption in Integrity and Data Encryption for PCIe has more detailed information on this. Figure 2: High-Level Flow for Partial Header Encryption 4. Randomization on IDE Address Association Register values: IDE Address Association Register 1/2/3 are supposed to be configured considering the memory address range of IDE partner ports. The fields of IDE address registers are split multiple values such as Memory Base Lower, Memory Limit Lower, Memory Base Upper, and Memory Limit Upper. IDE implementation can have multiple register blocks considering addresses with 32 or 64, different registers sizes, 0-255 selective streams, 0-15 address blocks, etc. This Randomization verification can help verify all the corner cases. Please refer to Figure 2. Figure 3: IDE Address Association Register 5. Random Faults During Encryption: Injecting random faults (e.g., dropped packets or timing mismatches) ensures the system can handle disruptions and prevent data leakage. Challenges of IDE Randomization and its Solution Randomization introduces a vast number of scenarios, making it computationally intensive to simulate every possibility. Constrained randomization limits random inputs to valid ranges while still covering edge cases. Again, using coverage-driven verification to ensure critical scenarios are tested without excessive redundancy. Verifying encrypted data with random inputs increases complexity. Encryption masks data, making it hard to verify outputs without compromising security. Here we can implement various IDE checks on the IDE callback to analyze encrypted traffic without decrypting it. Randomization can trigger unexpected failures, which are often difficult to reproduce. By using seed-based randomization, a specific seed generates a repeatable random sequence. This helps in reproducing and analyzing the behavior more precisely. Conclusion Randomization is a powerful technique in PCIe verification, ensuring robust validation of both data integrity and data encryption. It helps us to uncover subtle bugs and edge cases that a non-randomized testing might miss. In Cadence PCIe VIP, we support full-fledged IDE Verification with rigorous randomized verification that ensures data integrity. Robust and reliable encryption mechanisms ensure secure and efficient data communication. However, randomization also brings various challenges, and to overcome them we adopt a combination of constrained randomization, seed-based testing, and coverage-driven verification. As PCIe continues to evolve with higher speeds and focuses on high security demands, our Cadence PCIe VIP ensures it is in line with industry demand and verify high-performance systems that safeguard data in real-world environments with excellence. For more information, you can refer to Verification of Integrity and Data Encryption(IDE) for PCIe Devices and Industry's First Adopted VIP for PCIe 7.0 . More Information: For more info on how Cadence PCIe Verification IP and TripleCheck VIP enables users to confidently verify IDE, see our VIP for PCI Express , VIP for Compute Express Link for and TripleCheck for PCI Express For more information on PCIe in general, and on the various PCI standards, see the PCI-SIG website .

When the Arduino Mega2560 is added to the first serial port, the dynamic memory is 2000 bytes, and when the second serial serial is added, the dynamic memory is 4000 bytes. Now I need to add the third Serial serial port. The dynamic memory is 6000 bytes. Due to the many variables in the program itself, the dynamic memory is not enough. Please help me how to save the dynamic memory?

We are having some issues with deploying i. We are looking for the silent command switch for deployment including the licence agreement acceptance.

Ideally we would like a regular MSI that we could install for all users and not in the user content.

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.
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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.
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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.
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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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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.

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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

During a mixed-signal simulation, the analog engine usually dominates the simulation time and resources. If you need to run only the analog engine in several windows, or if you would like to to run multiple tests of the same circuit with different stimuli or test pattern, then you need to run the simulation multiple times. View this blog to know more about the the two advanced technologies that Spectre AMS Designer provides to help you improve the efficiency of your mixed-signal designs and to increase the simulation speed.(read more)

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

Read this blog to know how you can easily create and insert connect modules using Spectre AMS Designer with the Verilog-AMS standard language defined by Accellera. (read more)

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

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.

Read this blog to know more about the innovation behind Universal Connect Modules (UCM).(read more)

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.