Expert VHDL

• Design engineers wishing to improve the efficiency of their hardware designs and increase productivity
• Design and verification engineers who want to structure and write effective test environments to verify complex designs and systems

• A set of VHDL language features that go beyond what is taught on a basic training class
• A deeper understanding of how to apply VHDL language for design
  • enabling you to troubleshoot VHDL simulation and synthesis problems with ease
  • enabling code re-use
• The principles and details of how to approach the problem of design verification using VHDL
• How to structure and write large and complex VHDL structured verification environments
• The OSVVM and UVVM VHDL verification methodologies

This is an advanced language and methodology training class. Prior attendance of the Doulos Comprehensive VHDL class (or equivalent) is required, and at least 6 months of 'live' project experience using VHDL is strongly recommended. Delegates attending the Expert Design module must have knowledge and experience of register transfer level coding and synthesis using VHDL.

Doulos training materials are renowned as the most comprehensive and user friendly available. Their style, content and coverage is unique in the HDL training world and has made them sought after resources in their own right. Class fees include:

• Fully indexed class notes creating a complete reference manual
• Workbook full of practical examples to help you apply your knowledge
• Doulos Golden Reference Guide e-book for language, syntax, semantics and tips
• Tour guides (to support the tools and technologies of your choice)

If you would prefer a paperback version of your Doulos Golden Reference Guide, this can be purchased from the Doulos online shop.

Expert VHDL Design (Days 1-2)

RTL Synthesis and Synchronisation

Synthesis of Combinational Logic • Synthesis of Sequential Logic • Combinational and Sequential Together • Variables in Clocked Processes • How Many Registers? • Resolution Functions and Drivers • Unresolved Types • Synchronous Design • Synchronous Design Rules • Non-Synchronous Features • How Clever is Your Synthesis Tool? • Resource Sharing • Synthesizing Arithmetic - WYSIWYG • Eliminating the Mux • Shift Left/Right • Forcing an Implementation • Synthesis Attributes • Inference or Instantiation? • Static Timing Analysis • Timing Analysis Exceptions • Re-timing and Pipelining • Timing Analysis Exceptions • Hierarchy and Optimization • Registered Ports • Asynchronous Inputs • Input Hazard • • Metastability • Synchronizer in VHDL • Multiple Clock Domains • Transferring Data Between Clock Domains • Using a FIFO for Synchronisation • Synchronising Reset

Writing Readable Designs

VHDL Features for Abstraction • Record Types • Using Record Fields • Aggregates • Using Records for Wiring • Connecting Records • Inside a Peripheral • Multiplexed Bus Structure • Multiplexing Records • Representing Register Maps • Accessing Individual Registers • Accessing the Status Register • Collecting Registers Together • Alias • Using Aliases with Vectors • Using Alias with a Bus • Other Uses of Alias • Named Ranges • Using Named Ranges • Summary

Writing For Re-Use

Language-Level Reuse • Reusing Code Fragments • Standard Component Reuse • Procuring IP • Writing Reusable RTL IP • Reuse Tradeoffs • Example of a Regular Structure • Arrays of Arrays • Generics • Type Generics • Array Attributes • Generate Statement • More on Generate Statements • VHDL-2008 Generate Statements • Implementing the Behavior • Unconstrained Array Ports • Parameterizing the Data Width • VHDL-2008 Arrays • Multidimensional Arrays • Flattening Matrices • Multidimensional Arrays of Ports • Getting and Setting Rows • Architecture Using 2D Arrays • Instancing The Design • Optional Ports • Default On Component

Advanced Coding Styles

Subprograms • Procedures • Parameter Class, Mode, and Type • Subprogram Overloading • Signal Parameters • Synthesizing Procedures • Destructive Register Reads • Read Procedure • Procedure in FSM • Functions • Recursion • Recursive Function Example • Creating a Generic Counter • Creating a log2 Circuit • Recursive Instantiation • Recursive Component Declaration • Solving the Problem • Solving the Problem (VHDL-2008) • Synthesis Results

Finite State Machine Synthesis

State Transition Diagrams • Finite State Machines • A Simple Two Process Style • Another Two Process Style • One Process Style • State Machine Architecture • Comparison of Coding Styles • Easier Registered Outputs • Registered Outputs Using Local Variables • State Encoding • No Output Decoding • Unreachable States • Controlling Unreachable States • Explicit One Hot Style • Hand Optimised One Hot Style • Collision Signal • Too Many States? • FSM Summary

Packages and Configurations

Packages • Subprograms in Packages • Deferred Constants • VHDL-2008 Packages • Generics on a Package • Float Package • Fixed Package • Fixed Point Example • Use Clause Scope • Component Declaration and Instantiation • Component Declarations in a Package • Configuration • Default Binding Rules • Hierarchical Configurations • Nested Configurations • Port Name Changes • Type Conversions • Setting Generics • Configurations with Generate Statements

Properties and Assertions

Property versus Assertion • Applying Properties • Who Writes Properties? • Observability • A Simple Assertion • Simulation Checker or Monitor • Properties and the Specification • The Story So Far... • OVL • Using OVL with VHDL • OVL Packages • OVL Configuration • Instancing an Assertion • OVL VHDL Assertions • Example Assertions • PSL • The Elements of a Property • PSL Basics • The Structure of PSL • The Boolean Layer • Clocks and Default Clocks • Holds and Implication • next • The Temporal Layer • The Verification Layer • Verification Units • Modelling Layer • Using PSL with an HDL • Simulation of Temporal Properties • Summary of Benefits

Expert VHDL Verification (Days 3-5)

Functional Verification Methodology

What Is Verification? • Approaches to Verification • Verification Strategy • What to Verify? • Towards a Verification Plan • Don't Plan Everything • Identify Testcases • Verification Metrics • Coverage • Including Functional Coverage • Coverage Driven Verification • From Features to Tests • Checking • Verification Planning Revisited • The Basic Testbench • Verification Environment • Verification Methodologies • VHDL Methodology • Design for Verification • Glass Box Testing • Analysis to Choose Tests • Boundary Conditions & Corner Cases • Black Box Testing • Regression Testing • Stress Testing • Different Sorts of Stimulus

Subprograms and Protected Types

Using Abstraction in a Testbench • Subprograms • Procedures • Parameter Class, Mode, and Type • Subprogram Overloading • Signal Parameters • Functions • Subprograms in Packages • Impure functions • Protected types • Protected type body • Declaring a Shared Variable

More on File IO

The Basic Testbench • TEXTIO Output • Procedure READ • When READ Goes Wrong • Converting Values to Text Strings • Opening and Closing Files • Testing the File Open Status • Managing Text Files • Package STD_LOGIC_TEXTIO • Using Built-in Files • Reading Variable Length Data • Files Without Textio • Binary Files • VHDL-2008 File IO

Transaction Level Verification

Structuring Testbenches • Build the Complete Testbench • Monolithic Testbenches are Inflexible • Hide DUT Interface from Testcase • Layered Architecture • Transaction Level Testcase • Making a Transaction in VHDL • Accessing the Fields • Communicating Transactions • A Simple Example • What is a (VHDL) Transaction? • Interfacing Without Events • Generating Transactions • Using Procedures with Signals • A Systematic Approach • Non-blocking Procedures • Bus Functional Modelling • Bus Functional Model • Bus Functional Model Using Get • Synchronization • Synchronization Channel • Summary

More on BFMs - Time in Testbenches

Bus Functional Modelling • Wait Statements • Wait Statements and Time • Inspecting the Event Queue • Example SRAM Timing • Setup Time Check • Hold Time Check • Combined Setup / Hold Time Check • Pulse Width Check • Entity Declarations • Passive Processes • Using Vital Packages • Setup/Hold Check With Vital • What About Transactions? • Concurrent Signal Assignments • Drivers • How to "See" Drivers • Multiple Driver Issues • Longest Static Prefix • Sequential Signal Assignments • Inertial Delay • Identical Successive Assignments • Inertial Delays • Inertial and Transport Delays • Sampling Data - RTL • Postponed Processes

Behavioral Modelling and Checkers

Checking Results • Variable Latency • Arrays of Records • Queues • VHDL Queue Implementation • Using Queues • Coping with Out-of-Order Completion • Scoreboarding • Dynamic Memory Allocation • Access Types • Allocators • Deallocating Memory • Writing to a FIFO • Reading from a FIFO • Pointer Problems • Behavioural Modelling Example • Modelling the 2-wire Bus • Two Wire Slave Model • Protocol Implementation • Data Generation • Slave Procedure • Modelling State

Random Testing and Coverage

Verification - Reminder • Random Stimulus • Constraining Random Stimulus • Random Sequence of Valid Actions • Functional Coverage • Where Am I? • Concurrent Procedures • Coverage Procedure • Calling Coverage Procedures • Why Use Path Parameter?

Other Testbench Features

Completing our Methodology • Monitoring Internal Signals • Monitoring Internal Signals - VHDL-2002 • External Names • Monitoring Internal Signals - VHDL-2008 • Force and Release • The Objection Mechanism • Implementing Objection • Resolution Functions • Implementing Custom Objections • The Stop and Finish Procedures • Run-time Configuration • Implementing Run-time Configuration

Introduction to OSVVM

What is OSSVVM? • Randomization • Seed Management • Functional Coverage • Sampling • Specifying Bins • Specifying a Minimum Hit Count Per-Bin • Specifying Cross Bins • Specifying Ignore Bins • Displaying Coverage • Non-Repeating Randomize • Defining Explicit Weights • Weight by Coverage Shortfall • Logging • Redirecting to a Log File • Alerts • Stop Count • Disabling Alerts • Conditional Alerts • Hierarchical Alerts • Other Packages

Introduction to UVVM

What is UVVM? • Utility Library • Logging and Verbosity Control • Outputting Log Messages • Controlling Log Messages • Message IDs • Redirecting Log Messages • Alerts • Controlling Alerts • Reporting Alerts • Checks • Awaits • String Handling • Randomization • Signal Generators • Synchronization • BFM Common Package • Warnings • UVVM VVC Framework • UVVM Structure • UVVM Test Harness • UVVM Test Bench • Test Sequencer • UVVM Command Distribution • Example Command Distribution Methods • UVVM VHDL Network Model • VIP • Feature Comparison