Memory is an essential part of electronic industry. Since, the processors used in various high performance
PCs, network applications and communication equipment require high speed memories. The type of
memory used depends on system architecture, and its applications. This paper presents an SRAM
architecture known as Zero Bus Turnaround (ZBT). This ZBT SRAM is mainly developed for networking
applications where frequent READ/WRITE transitions are required. The other single data rate SRAMs are
inefficient as they require idle cycles when they frequently switch between reading and writing to the
memory. This controller is simulated on the Spartan 3 device. And the performance analysis is done on the
basis of area, speed and power.
In many I/O interfacing applications and certainly in data acquisation system. it is often necessary to transfer data to or from an interface at data rates higher than those possible using simple programmed I/O loops
DMA stands for Direct memory access and is a method of transferring data from the computers RAM to another part of the computer without processing it using the CPU.
In many I/O interfacing applications and certainly in data acquisation system. it is often necessary to transfer data to or from an interface at data rates higher than those possible using simple programmed I/O loops
DMA stands for Direct memory access and is a method of transferring data from the computers RAM to another part of the computer without processing it using the CPU.
Direct Memory Access (DMA)-Working and ImplementationShubham Kumar
DMA is an important functionality of any computing system involving transfer of data from/to an I/O device. In this presentation, a brief description has been provided regarding how the DMA functionality is implemented on a normal PC as well as on an Intel Quark SoC based small Embedded System.Different implementations of the DMA functionality depend on the Controller Hub present on the SouthBridge of the MotherBoard of the respective platform.For example->DMA implementation in Intel ICH7 is different from those in Intel ICH to Intel ICH6. In the slides, "Galileo" refers to the Intel Galileo Board containing Intel Quark SoC. Intel Galileo Board contains Designware DMA controllers." dmatest.c " is a memory-to-memory data transfer test driver implementing DMA. This module is loaded and then memcpy is checked using dmesg. Do take a look at the "External Links and References" given at the end of the PPT.
This PPT describe the use of direct memory access and how the input and output devices exchange the data with processor without interruption like waiting for address fetch.
Memory map selection of real time sdram controller using verilog full project...rahul kumar verma
full report on Memory map selection of real time SDRAM controller using verilog which was my project.If you want any help email me @ rahulverma2512@gmail.com
Tracking cancer patients medical history using wireless emerging technology ...VLSICS Design
The principal objective of this paper is to present an effective solution for storing and retrieving a cancer
patient’s medical history in hospitals, clinics and wherever else need be. We have used latest technologies like Near Field Communication (NFC) as a medium for communication, MySQL server for storing the database i.e. EHR (Electronic Health Record) of patients and lastly an Android application which will provide the interface for the same.
There are many ways in attracting visitors in organic ways. Some of the listed methods may be more appealing to you and some may be the one which can work best.
Although some of the strategies listed aren't easy and fast to perform, you have to look at thing positively - and that is to gain more visitors, make them come back for more and even convert them into leads.
What has been the best traffic source for you?
Direct Memory Access (DMA)-Working and ImplementationShubham Kumar
DMA is an important functionality of any computing system involving transfer of data from/to an I/O device. In this presentation, a brief description has been provided regarding how the DMA functionality is implemented on a normal PC as well as on an Intel Quark SoC based small Embedded System.Different implementations of the DMA functionality depend on the Controller Hub present on the SouthBridge of the MotherBoard of the respective platform.For example->DMA implementation in Intel ICH7 is different from those in Intel ICH to Intel ICH6. In the slides, "Galileo" refers to the Intel Galileo Board containing Intel Quark SoC. Intel Galileo Board contains Designware DMA controllers." dmatest.c " is a memory-to-memory data transfer test driver implementing DMA. This module is loaded and then memcpy is checked using dmesg. Do take a look at the "External Links and References" given at the end of the PPT.
This PPT describe the use of direct memory access and how the input and output devices exchange the data with processor without interruption like waiting for address fetch.
Memory map selection of real time sdram controller using verilog full project...rahul kumar verma
full report on Memory map selection of real time SDRAM controller using verilog which was my project.If you want any help email me @ rahulverma2512@gmail.com
Tracking cancer patients medical history using wireless emerging technology ...VLSICS Design
The principal objective of this paper is to present an effective solution for storing and retrieving a cancer
patient’s medical history in hospitals, clinics and wherever else need be. We have used latest technologies like Near Field Communication (NFC) as a medium for communication, MySQL server for storing the database i.e. EHR (Electronic Health Record) of patients and lastly an Android application which will provide the interface for the same.
There are many ways in attracting visitors in organic ways. Some of the listed methods may be more appealing to you and some may be the one which can work best.
Although some of the strategies listed aren't easy and fast to perform, you have to look at thing positively - and that is to gain more visitors, make them come back for more and even convert them into leads.
What has been the best traffic source for you?
Dynamic floating output stage for low power buffer amplifier for lcd applicationVLSICS Design
This topic proposes low-power buffer means low quiescent current buffer amplifier. A dynamic floating current node is used at the output of two-stage amplifier to increase the charging and discharging of output capacitor as well as settling time of buffer. It is designed for 10 bit digital analog converter to support for LCD column driver it is implemented in 180 nm CMOS technology with the quiescent current of 5 μA for 30 pF capacitance, the settling time calculated as 4.5μs, the slew rate obtained as 5V/μs and area on chip is 30×72μ.
An efficient multi resolution filter bank based on da based multiplicationVLSICS Design
Multi-resolution filter bank (MRFB)-based on the fast filter bank design can be used for multiple resolution
spectrum sensing. MRFB overcomes the constraint of fixed sensing resolution in spectrum sensors based
on conventional discrete Fourier transform filter banks (DFTFB) without hardware re-implementation.
Multipliers have a greater impact on complexity and performance of the design because a large number of
constant multiplications are required in the multiplication of filter coefficients with the filter input.
Modified multiplier architecture Distributed Arithmetic(DA) is used to improve the efficiency
Design of a novel current balanced voltage controlled delay elementVLSICS Design
This paper presents a design of fast voltage controlled delay element based on modified version of low
noise Current Balanced Logic (CBL). This delay element provides identical rising and falling edge delays
controlled by the single control voltage. The post layout tunable delay range is from 140 ps to 800 ps over
control voltage range of 0 to 2.1 V. An analysis for the delay element is also presented, which is in
agreement with the simulated delays. A Delay Lock Loop (DLL) is designed using this delay element to
verify its performance.
ANALYSIS OF SMALL-SIGNAL PARAMETERS OF 2-D MODFET WITH POLARIZATION EFFECTS F...VLSICS Design
An improved analytical two dimensional (2-D) model for AlGaN/GaN modulation doped field effect
transistor (MODFET) has been developed. The model is based on the solution of 2-D Poisson’s equation.
The model includes the spontaneous and piezoelectric polarization effects. The effects of field dependent
mobility, velocity saturation and parasitic resistances are included in the current voltage characteristics of
the developed two dimensional electron gas (2-DEG) model. The small-signal microwave parameters have
been evaluated to determine the output characteristics, device transconductance and cut-off frequency for
50 nm gate length. The peak transconductance of 165mS/mm and a cut-off frequency of 120 GHz have been
obtained. The results so obtained are in close agreement with experimental data, thereby proving the
validity of the model.
DESIGN OF PARITY PRESERVING LOGIC BASED FAULT TOLERANT REVERSIBLE ARITHMETIC ...VLSICS Design
Reversible Logic is gaining significant consideration as the potential logic design style for implementation
in modern nanotechnology and quantum computing with minimal impact on physical entropy .Fault
Tolerant reversible logic is one class of reversible logic that maintain the parity of the input and the
outputs. Significant contributions have been made in the literature towards the design of fault tolerant
reversible logic gate structures and arithmetic units, however, there are not many efforts directed towards
the design of fault tolerant reversible ALUs. Arithmetic Logic Unit (ALU) is the prime performing unit in
any computing device and it has to be made fault tolerant. In this paper we aim to design one such fault
tolerant reversible ALU that is constructed using parity preserving reversible logic gates. The designed
ALU can generate up to seven Arithmetic operations and four logical operations.
EVALUATION OF OPTICALLY ILLUMINATED MOSFET CHARACTERISTICS BY TCAD SIMULATIONVLSICS Design
In this paper we report effect of optical illumination on Silicon MOSFET. The MOSFET has been studied in
respect of current voltage, transconductance admittance and scattering parameters. Gain analysis of the
Silicon MOSFET is done in dark and under optical illumination. The device is fabricated using ATHENA™
process simulator and the device simulation is performed using ATLAS™ from SILVACO international.
The simulation results indicate potential of MOSFET as optically sensitive structure which can be used
for increase in data transmission/reception rates, reduction of interconnect delays, elimination of clock
skew, or as a photodetector for optoelectronic applications at low and radio frequency.
A DAPTIVE S UPPLY V OLTAGE M ANAGEMENT F OR L OW P OWER L OGIC C IRCU...VLSICS Design
With the rise in demand of portable hand held devic
es and with the rise in application of wireless sen
sor
networks and RFID reduction of total power consumpt
ion has become a necessity. To save power we
operate the logic circuitry of our devices at sub-t
hreshold. In sub-threshold the drain current is
exponentially dependent on the threshold voltage he
nce the threshold variation causes profound variati
on
of I
ON
and I
OFF
the ratio of which affect the speed of a circuit d
rastically. So to mitigate this problem we
present a adaptive power management circuit which w
ill determine the minimum required supply voltage
to meet the timing requirement. Also to reduce the
power overhead and avoid bulky coil and EMI noise
we used the switch capacitor power regulator to reg
ulate and manage power instead of linear dropout
(LDO) and Inductor base switch mode power converter
Here are the elements you need to get back again when your rankings went down. All these onsite and offsite factors are important in making your website rank.
Energy Efficient Full Adder Cell Design with Using Carbon Nanotube Field Effe...VLSICS Design
Full Adder is one of the critical parts of logical and arithmetic units. So, presenting a low power full adder
cell reduces the power consumption of the entire circuit. Also, using Nano-scale transistors, because of
their unique characteristics will save energy consumption and decrease the chip area. In this paper we
presented a low power full adder cell by using carbon nanotube field effect transistors (CNTFETs).
Simulation results were carried out using HSPICE based on the CNTFET model in 32 nanometer
technology in Different values of temperature and VDD.
SEO has plenty to teach us about life, work, relationships, and everything in between. For newly graduates out there, check out these words of wisdom from a veteran SEO expert.
An operational amplifier with recycling folded cascode topology and adaptive ...VLSICS Design
This paper presents a highly adaptive operational amplifier with high gain, high bandwidth, high speed
and low power consumption. By adopting the recycling folded cascode topology along with an adaptivebiasing
circuit, this design achieves high performance in terms of gain-bandwidth product (GBW) and slew
rate (SR). This single stage op-amp has been designed in 0.18μm technology with a power supply of 1.8V
and a 5pF load. The simulation results show that the amplifier achieved a GBW of 335.5MHz, Unity Gain
Bandwidth of 247.1MHz and a slew rate of 92.8V/μs.
Vlsics040307DESIGN AND IMPLEMENTATION OF CAR PARKING SYSTEM ON FPGAVLSICS Design
As, the number of vehicles are increased day by day in rapid manner. It causes the problem of traffic
congestion, pollution (noise and air). To overcome this problem A FPGA based parking system has been
proposed. In this paper, parking system is implemented using Finite State Machine modelling. The system
has two main modules i.e. identification module and slot checking module. Identification module
identifies the visitor. Slot checking module checks the slot status. These modules are modelled in HDL
and implemented on FPGA. A prototype of parking system is designed with various interfaces like sensor
interfacing, stepper motor and LCD.
Design, Validation and Correlation of Characterized SODIMM Modules Supporting...IOSR Journals
Abstract : In any computing environment, it is necessary for the processor to have fast accessible RAM that allows temporary storage of data. DDR3- SODIMM module is a key component in the memory interface and is becoming increasingly important in enabling higher speeds. Considering higher bandwidths and speeds more than 1GHz, DDR3 is enabling poses more and more high speed signaling and design challenges. Characterized SODIMM module need to be designed to understand and analyze the impact of SODIMM parameters at higher speeds and thereby define more robust memory interface. This will include simulation, board design, validation and results correlation and involves high speed simulation and validation methodologies. Keywords – Validation, Correlation, DDR3, Characterized SODIMM, Signal Integrity
IOSR journal of VLSI and Signal Processing (IOSRJVSP) is a double blind peer reviewed International Journal that publishes articles which contribute new results in all areas of VLSI Design & Signal Processing. The goal of this journal is to bring together researchers and practitioners from academia and industry to focus on advanced VLSI Design & Signal Processing concepts and establishing new collaborations in these areas.
Design and realization of microelectronic systems using VLSI/ULSI technologies require close collaboration among scientists and engineers in the fields of systems architecture, logic and circuit design, chips and wafer fabrication, packaging, testing and systems applications. Generation of specifications, design and verification must be performed at all abstraction levels, including the system, register-transfer, logic, circuit, transistor and process levels
Design and Simulation Low power SRAM Circuitsijsrd.com
SRAMs), focusing on optimizing delay and power. As the scaling trends in the speed and power of SRAMs with size and technology and find that the SRAM delay scales as the logarithm of its size as long as the interconnect delay is negligible. Non-scaling of threshold mismatches with process scaling, causes the signal swings in the bitlines and data lines also not to scale, leading to an increase in the relative delay of an SRAM, across technology generations. Appropriate methods for reduction of power consumption were studied such as capacitance reduction, very low operating voltages, DC and AC current reduction and suppression of leakage currents to name a few.. Many of reviewed techniques are applicable to other applications such as ASICs, DSPs, etc. Battery and solar-cell operation requires an operating voltage environment in low voltage area. These conditions demand new design approaches and more sophisticated concepts to retain high device reliability. The proposed techniques (USRS and LPRS) are topology based and hence easier to implement.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Paper chosen for DesignCon 2015. Critical Memory Performance Metrics for DDR4. Is DDR4 the end of the DDR line of memory technologies? If so then stretching DDR4 to give that much more performance is critical. Discussed in this paper is how to measure the intricate performance metrics of your DDR4 system and why they matter. Understanding these critical parameters can lead to better system design, memory controller architecture and software design. Metrics such as Power Management, Page Hits, Bank Group and Bank Utilization, Multiple Open Bank Analysis, Data Bus Utilization and overhead on a DDR4 memory bus will be demonstrated and discussed.
International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
Securing your Kubernetes cluster_ a step-by-step guide to success !KatiaHIMEUR1
Today, after several years of existence, an extremely active community and an ultra-dynamic ecosystem, Kubernetes has established itself as the de facto standard in container orchestration. Thanks to a wide range of managed services, it has never been so easy to set up a ready-to-use Kubernetes cluster.
However, this ease of use means that the subject of security in Kubernetes is often left for later, or even neglected. This exposes companies to significant risks.
In this talk, I'll show you step-by-step how to secure your Kubernetes cluster for greater peace of mind and reliability.
Transcript: Selling digital books in 2024: Insights from industry leaders - T...BookNet Canada
The publishing industry has been selling digital audiobooks and ebooks for over a decade and has found its groove. What’s changed? What has stayed the same? Where do we go from here? Join a group of leading sales peers from across the industry for a conversation about the lessons learned since the popularization of digital books, best practices, digital book supply chain management, and more.
Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
Observability Concepts EVERY Developer Should Know -- DeveloperWeek Europe.pdfPaige Cruz
Monitoring and observability aren’t traditionally found in software curriculums and many of us cobble this knowledge together from whatever vendor or ecosystem we were first introduced to and whatever is a part of your current company’s observability stack.
While the dev and ops silo continues to crumble….many organizations still relegate monitoring & observability as the purview of ops, infra and SRE teams. This is a mistake - achieving a highly observable system requires collaboration up and down the stack.
I, a former op, would like to extend an invitation to all application developers to join the observability party will share these foundational concepts to build on:
zkStudyClub - Reef: Fast Succinct Non-Interactive Zero-Knowledge Regex ProofsAlex Pruden
This paper presents Reef, a system for generating publicly verifiable succinct non-interactive zero-knowledge proofs that a committed document matches or does not match a regular expression. We describe applications such as proving the strength of passwords, the provenance of email despite redactions, the validity of oblivious DNS queries, and the existence of mutations in DNA. Reef supports the Perl Compatible Regular Expression syntax, including wildcards, alternation, ranges, capture groups, Kleene star, negations, and lookarounds. Reef introduces a new type of automata, Skipping Alternating Finite Automata (SAFA), that skips irrelevant parts of a document when producing proofs without undermining soundness, and instantiates SAFA with a lookup argument. Our experimental evaluation confirms that Reef can generate proofs for documents with 32M characters; the proofs are small and cheap to verify (under a second).
Paper: https://eprint.iacr.org/2023/1886
Dev Dives: Train smarter, not harder – active learning and UiPath LLMs for do...UiPathCommunity
💥 Speed, accuracy, and scaling – discover the superpowers of GenAI in action with UiPath Document Understanding and Communications Mining™:
See how to accelerate model training and optimize model performance with active learning
Learn about the latest enhancements to out-of-the-box document processing – with little to no training required
Get an exclusive demo of the new family of UiPath LLMs – GenAI models specialized for processing different types of documents and messages
This is a hands-on session specifically designed for automation developers and AI enthusiasts seeking to enhance their knowledge in leveraging the latest intelligent document processing capabilities offered by UiPath.
Speakers:
👨🏫 Andras Palfi, Senior Product Manager, UiPath
👩🏫 Lenka Dulovicova, Product Program Manager, UiPath
A tale of scale & speed: How the US Navy is enabling software delivery from l...sonjaschweigert1
Rapid and secure feature delivery is a goal across every application team and every branch of the DoD. The Navy’s DevSecOps platform, Party Barge, has achieved:
- Reduction in onboarding time from 5 weeks to 1 day
- Improved developer experience and productivity through actionable findings and reduction of false positives
- Maintenance of superior security standards and inherent policy enforcement with Authorization to Operate (ATO)
Development teams can ship efficiently and ensure applications are cyber ready for Navy Authorizing Officials (AOs). In this webinar, Sigma Defense and Anchore will give attendees a look behind the scenes and demo secure pipeline automation and security artifacts that speed up application ATO and time to production.
We will cover:
- How to remove silos in DevSecOps
- How to build efficient development pipeline roles and component templates
- How to deliver security artifacts that matter for ATO’s (SBOMs, vulnerability reports, and policy evidence)
- How to streamline operations with automated policy checks on container images
In his public lecture, Christian Timmerer provides insights into the fascinating history of video streaming, starting from its humble beginnings before YouTube to the groundbreaking technologies that now dominate platforms like Netflix and ORF ON. Timmerer also presents provocative contributions of his own that have significantly influenced the industry. He concludes by looking at future challenges and invites the audience to join in a discussion.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
PHP Frameworks: I want to break free (IPC Berlin 2024)Ralf Eggert
In this presentation, we examine the challenges and limitations of relying too heavily on PHP frameworks in web development. We discuss the history of PHP and its frameworks to understand how this dependence has evolved. The focus will be on providing concrete tips and strategies to reduce reliance on these frameworks, based on real-world examples and practical considerations. The goal is to equip developers with the skills and knowledge to create more flexible and future-proof web applications. We'll explore the importance of maintaining autonomy in a rapidly changing tech landscape and how to make informed decisions in PHP development.
This talk is aimed at encouraging a more independent approach to using PHP frameworks, moving towards a more flexible and future-proof approach to PHP development.
Enhancing Performance with Globus and the Science DMZGlobus
ESnet has led the way in helping national facilities—and many other institutions in the research community—configure Science DMZs and troubleshoot network issues to maximize data transfer performance. In this talk we will present a summary of approaches and tips for getting the most out of your network infrastructure using Globus Connect Server.
Alt. GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using ...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
Removing Uninteresting Bytes in Software FuzzingAftab Hussain
Imagine a world where software fuzzing, the process of mutating bytes in test seeds to uncover hidden and erroneous program behaviors, becomes faster and more effective. A lot depends on the initial seeds, which can significantly dictate the trajectory of a fuzzing campaign, particularly in terms of how long it takes to uncover interesting behaviour in your code. We introduce DIAR, a technique designed to speedup fuzzing campaigns by pinpointing and eliminating those uninteresting bytes in the seeds. Picture this: instead of wasting valuable resources on meaningless mutations in large, bloated seeds, DIAR removes the unnecessary bytes, streamlining the entire process.
In this work, we equipped AFL, a popular fuzzer, with DIAR and examined two critical Linux libraries -- Libxml's xmllint, a tool for parsing xml documents, and Binutil's readelf, an essential debugging and security analysis command-line tool used to display detailed information about ELF (Executable and Linkable Format). Our preliminary results show that AFL+DIAR does not only discover new paths more quickly but also achieves higher coverage overall. This work thus showcases how starting with lean and optimized seeds can lead to faster, more comprehensive fuzzing campaigns -- and DIAR helps you find such seeds.
- These are slides of the talk given at IEEE International Conference on Software Testing Verification and Validation Workshop, ICSTW 2022.
DESIGN AND PERFORMANCE ANALYSIS OF ZBT SRAM CONTROLLER
1. International Journal of VLSI design & Communication Systems (VLSICS) Vol.4, No.3, June 2013
DOI : 10.5121/vlsic.2013.4310 102
DESIGN AND PERFORMANCE ANALYSIS OF ZBT
SRAM CONTROLLER
Smriti Sharma1
and Balwinder Singh2
1,2
Centre for Development of Advanced Computing, India
Sharma.smriti21@gmail.com, Balwinder.cdacmohali@gmail.com
ABSTRACT
Memory is an essential part of electronic industry. Since, the processors used in various high performance
PCs, network applications and communication equipment require high speed memories. The type of
memory used depends on system architecture, and its applications. This paper presents an SRAM
architecture known as Zero Bus Turnaround (ZBT). This ZBT SRAM is mainly developed for networking
applications where frequent READ/WRITE transitions are required. The other single data rate SRAMs are
inefficient as they require idle cycles when they frequently switch between reading and writing to the
memory. This controller is simulated on the Spartan 3 device. And the performance analysis is done on the
basis of area, speed and power.
KEYWORDS
ZBT SRAM, performance analysis, READ/WRITE transitions, speed, area & power
1. INTRODUCTION
The emergence of networking and communication systems requiring higher bandwidth interfaces
and lower latency for peripheral components lead to the implementation of designs using high
throughput memory with efficient bus utilization and resulted in the development of a new SRAM
architecture known as ZBT. The previous generation of static memory types is inefficient as they
require idle cycles when they frequently switch between reading from and writing to the memory.
IDT, Micron, and Motorola have developed the ZBT SRAM architecture to address this problem.
ZBT SRAM is offered with two intefaces they are: Flowthrough and Pipelined SRAM. Pipelined
interface requires two clock cycles for read and two clock cycles for write operations where as
flowthrough requires single clock cycle for both read and write operation, respectively.
Flowthrough provides one clock cycle less latency then pipelining, where as pipelining provides
high clock to data access.
Due to the fast, low latency access to the CPU, SRAMS are widely used in data communication
systems. ZBT SRAM architecture was developed to improve the bandwidth of the interface and
overcome the several limitations. ZBT SRAM technology was developed for operation in the
applications where data rates are below 200MHz.
Synchronous SRAM basically comes under two different flavors: Single data rate SRAMs and
Double data rate SRAMs [5].
2. International Journal of VLSI design & Communication Systems (VLSICS) Vol.4, No.3, June 2013
102
The single Data Rate SRAMs are:
• Pipelined vs. Flowthrough SRAMs
• Burst SRAMs
• Network SRAMs - NoBL™/ZBT™ SRAMs.
The Double Data Rate SRAMs are:
• Standard DDR SRAMs
• QDR™ SRAMs.
Table 1. Comparison of ZBT/NoBL SRAM with other single data rate synchronous SRAMs
2. ZBT SRAM CONTROLLER
2.1. A Primer on ZBT SRAM
The term "Zero Bus Turnaround" was invented by IDT in October 1996. IDT, Micron, and
Motorola are the three companies that developed the ZBT technologies independently, and are
offering compatible ZBT products based upon the same architecture. ZBT SRAM provides the
maximum system throughput by utilizing every bus cycles. There is no turnaround cycles when
switching between read and write cycles. So this feature is beneficial in various applications with
random, intermixed read and writes operations on the data bus as compared to long bursts of
reads and writes. Some of the applications are LAN and WAN switching, gigabit switching,
network interface cards, ATM switching, switch or hub-shared fabric and router tables. ZBT
SRAM comes in two varieties i.e. pipelined and flowthrough. Flowthrough devices have shorter
latency than pipelined devices, but pipelined devices can operate at higher frequencies. Control
signals on both types are identical, and are simpler than Sync Burst. Pipelined ZBT SRAMs are
late-late-read RAMs in the sense that data appears two clock cycles after address. In order to
allow interleaved reads and writes, it is also called late-late-write RAM. Flowthrough ZBT
SRAM is late-read RAMs in that data appears one clock cycle after address. They are also called
late-write RAMs [10].
2.2. Block Diagram of ZBT SRAM Controller
In figure 1, the various low level modules of ZBT SRAM Controller are shown. An overview of
various signals used in ZBT SRAM controller are control, clock, address and data signals to give
an overall functionality description. The ZBT SRAM controller accepts SRAM request from user
and performs pipelined or flowthrough read and write operations, respectively. The controller
ensures that correct latencies and bus turnaround timings are met. Clock signal which comes
under the module clk_ctrl is used for all clocking purposes including reads and writes. All these
timing references are made at the rising edge of clock. Pipe_stage covers the control signals, and
Other Single Data Rate
Synchronous SRAMs
ZBT/NoBL Synchronous
SRAM
Most effective for Burst
Reads/Writes for Level 2 Cache
Ideal for Networking
applications
Ideal for Dominated Read or
Write
Ideal for Read/Write ratio
of 1
Latency occurs when switching
from write to read operation
Enables faster memory
performance-eliminates the
latency cycle
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there are three primary types of control signals to interface with memory controllers. They are
wr_n, mode and adv_load. Wr_n is a synchronous input, asserted LOW for write operation and
asserted HIGH for read operation. Mode is a synchronous signal used to select the mode in which
memory is working i.e. either pipelined or flowthrough mode. Address signals comes under
addr_ctrl_out which uses one synchronous bus input for all read and write operations with
memory device. And last one is data signals that come under data_inout module which uses one
synchronous bidirectional data bus for all read and write operations to and from the memory
device. Further, description of these modules is given below:
• Pipe_delay provides the proper delay for the input data, depending on whether the
controller is working in the pipelined or flowthrough mode.
• Addr_ctrl_out registers the address and control signals before outputting them to the ZBT
SRAM.
• Data_inout registers the input and output user signals for speed purposes in a stand-alone
controller configuration.
• Clk_ctrl provides clock to all modules.
Figure 1. Block Diagram of ZBT SRAM Controller
2.3. ZBT SRAM Sequence
ZBT SRAM uses one system clock input for all clocking purposes including read and write
operations. Both read and write commands are sent on the rising edge of the clock. Here read data
bus and write data bus are the same. Figure 2(a) shows the timing of read and write operations in
the flowthrough ZBT SRAM. In this when address is loaded on the address bus then read/write
will be done after one clock cycle as shown in the fig below. Figure 2(b) shows the timing of read
and write operations in the pipelined ZBT SRAM. In this when address is loaded on the address
bus and read/write signal is given then read/write is done after two clock cycles as shown in the
figure below.
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Figure 2(a): Flowthrough operation
Figure 2(b): Pipelined Operation
3. RELATED WORK
Many researchers have explored the reading and writing from and to the memory in the past with
different SRAMs memory architectures and controllers designed. Some of the papers and
datasheets are discussed below. Kang Li et. al. [2] proposed a new architecture of shared QDR
SRAM controller to make the SRAM Controller suitable for higher bandwidth and speed network
communication. In this arbitration method is used to simultaneous read and write operation to the
memory can be executed, and tag architecture is adopted to keep the special sequence of the
SRAM reference. Thus, the high utilization of bandwidth is done. Ravi Khatwal [1] has worked
to design high speed and low power consumption memory for embedded system. And by using
Xilinx tool, they calculate the access time that is required for selecting a word and reading it. In
this, synchronous static RAM has easily read/writes operation in efficient manner. Abhishek
kumar et. al. [4] has worked to design a kind of SDRAM controller. This controller provides a
synchronous command interface to the SDRAM memory along with several control signals. It has
two main control schemes, command generation and signal generation, simultaneously these
modules provide signal to the data path for data transfer. In this memory system operates at
double the frequency of processor, without affecting the performance, we can reduce the data bus
size. Ranjan Chakraborty [3] discusses about the design of an 8-bit First In First Out Memory
which may be utilized in various electronic components and gadgets. In the first stage of design,
the RAM 16X4S chips are introduced in the design but here the numbers of bits were reduced
from 16 to 8 as it was not being possible to carry the previous number of bits in this renewed
design.
4. PROPOSED WORK
The design of the ZBT SRAM controller has been done successfully on Xilinx ISE Design Suite
12.4. The main contributions of this work are as follows:
1). ZBT SRAM Controller design: At first, we have to understand the working of address module.
Secondly, the most important block is datapath module, the most difficult aspect of ZBT SRAM
controller design is to transmit and capture data at proper time delay according to the mode
selected.
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2). ZBT SRAM Controller analysis: After completing the design process, analysis part is done.
Analysis can be done on the basis of speed, area, and power consumed. And also the frequency at
which it is working.
5. HARDWARE DESIGN AND VHDL MODEL
The hardware design of ZBT SRAM Controller has gone through three different stages. In the
first stage, the VHDL code is written and implemented for Flowthrough SRAM. In the second
stage, the VHDL code is written and implemented for Pipelined SRAM. In the third and the final
stage, Controller is designed and implemented for both techniques. Figure 3 shows the RTL
Schematic for ZBT SRAM Controller.
Figure 3: RTL schematic of ZBT SRAM Controller
• clk is the input clock signal to the controller.
• oe_n is the output enable signal.
• ce_n is the chip enable signal.
• wr_n is the read/write signal.
• mode is the mode select signal i.e. either flowthrough or pipelined.
• adv_load is the advance or load pin to the controller.
• addr is the user defined address i.e. the input address to the controller.
• data_inout is the data out from the controller during read process or data in from the user
to the memory during write process.
6. SIMULATION RESULTS
Figure 4(a) shows the VHDL simulation of controller in flowthrough mode of ZBT SRAM
Controller. Here, the period of clk given is 1us. Here control signals are occurred either at high-
to-low transition or at low-to-high transitions. Oe_n is the output enable signal which is active
low signal. It is required for read operation, to enable the output. Ce_n is the chip enable signal,
which is also active low signal. Wr_n is the read/write signal, when LOW, it worked as write
signal and when HIGH, it worked as read signal. Adv_load is the advance or load signal, which
when low, loads the new address on address bus and when high, advances the address present on
the address bus. As Addr is the input pin and therefore the advanced address is not shown on this
pin only the loaded address is visible. Data_inout is the data bus, which is bidirectional in nature
that same data bus is used in both read and writes cycles. Reg1 and reg2 are the memory array for
flowthrough and pipelined ZBT SRAM, respectively. The simulation results, shown below are the
read operation in flowthrough mode that is read operation take only one clock cycle for its
operation.
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Figure 4(a): Read/Write in Flowthrough ZBT SRAM
Figure 4(b) shows the VHDL simulation of controller in pipelined mode of ZBT SRAM
Controller. This simulation results, shows the read operation in pipelined mode that is in this read
operation takes two clock cycles for its operation.
Figure 4(b): Read/Write in Pipelined ZBT SRAM
7. RESULTS AND DISCUSSIONS
Table 2(a) shows the device utilization summary that includes the utilization of slices, slice flip
flops, 4 input LUTs, bonded IOBs and GCLKs. Table 2(b) shows the timing summary, which
includes minimum time period, maximum frequency needed , minimum time required by input
before clock, maximum time that output required after clock and maximum combinational path
delay.
Table 2(a): Device Utilization Summary
Logic Utilization Used Available Utilization
Number of Slices 148 768 19%
Number of Slice Flip Flops 201 1536 13%
Number of 4 input LUTs 161 1536 10%
Number of bonded IOBs 25 124 20%
Number of GCLKs 1 8 12%
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Table 2(b): Timing Summary
Timing ZBT SRAM
Controller
Speed Grade -4
Minimum period 5.007ns
Maximum Frequency 199.720MHz
Minimum input arrival time before clock 6.598ns
Maximum output required time after clock 11.325ns
Maximum combinational path delay 12.538ns
8. CONCLUSIONS
In this paper, we have designed various modules of ZBT SRAM Controller and verified the
required functionality by using test bench. The main challenging part is to meet all the timing
requirements of various modules. We have met all the timing requirements efficiently. All the
design features are met according to the requirements. The device utilization summary is given in
Table2 (a) and timing summary is given in Table2 (b). And the total power consumed is 243.76
mW.
REFERENCES
[1] Ravi Khatwal and Manoj Kumar Jain. Article, March 2013: “An Efficient Synchronous Static
Memory design for Embedded System”. International Journal of Computer Applications 66(18):39-
45. Published by Foundation of Computer Science, New York, USA.
[2] Kang Li; Hongye Jia; Honghu Gong; Jiangyi Shi; Peijun Ma, 28-30 Oct. 2011 "Optimization of QDR
SRAM Controller in Network Processor," Computational Intelligence and Design (ISCID), 2011
Fourth International Symposium on , vol.1, pp.254-257. DOI :10.1109/ISCID.2011.71
[3] Ranjan Chakraborty, July 6-8, 2011 “Design and implementation of 8-bit read-write memory using
FIFO Algorithm,” Proceedings of the World Congress on Engineering 2011 Vol II WCE 2011,
London, U.K.
[4] Abhishek Kumar, Yogesh. E. Wankhede, Kirti Shinde P., Nisha Sarwade, 2010 “Design of SDRAM
Memory Controller using VHDL,” International Journal of Computer Science and Application Issue,
pp. 184-189, ISSN 0974-0767.
[5] Application Note, 2006 “Introduction to Cypress SRAMs – AN1116”.
[6] Volnei A. Pedroni, 2004 “Circuit Design with VHDL”, MIT Press Cambridge, Massachusetts
London, England.
[7] Altera, 2004 “ZBT SRAM Controller Reference Design for Stratix & Stratix GX Devices”.
[8] JOHN F. WAKERLY, 2002 “Digital design principles & practices”, 3rd Edition, Pearson Education
Asia.
[9] Shekhar Bapat, January 10, 2000 “Synthesizable 200 MHz ZBT SRAM Interface,” XAPP136 (v2.0).
[10] Shekhar Bapat, April 6, 1999 “Synthesizable 143 MHz ZBT* SRAM Interface,” XAPP136, (Version
1.1).
[11] Datasheet for ZBT SRAM Controller, Softjin enabling electronic design.
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[12] Application Note, 1997 “Understanding Static RAM Operation
Authors Biography
Balwinder Singh has obtained his Bachelor of Technology degree from National
Institute of Technology, Jalandhar and Master of Technology degree from University
Centre for Inst. & Microelectronics (UCIM), Punjab University, Chandigarh in 2002 and
2004 respectively. He is currently serving as Senior Engineer in Centre for Development
of Advanced Computing (CDAC), Mohali and is a part of the teaching faculty and also
pursuing PhD from GNDU Amritsar. He has 8+ years of teaching experience to both
undergraduate and postgraduate students. Singh has published three books and many papers in the
International & National Journal and Conferences. His current interest includes Genetic algorithms, Low
Power techniques, VLSI Design & Testing, and System on Chip.
Smriti Sharma received the B.Tech (Electronics and Communication Engineering)
degree from the Inderprastha Engineering College, Sahibabad affiliated to Uttar Pradesh
Technical University, in 2009, and presently she is doing M.Tech (VLSI design) degree
from Centre for Development of Advanced Computing (CDAC), Mohali and working on
her thesis work. Her area of interest is VLSI Design.