IAY0600 DIGITAL SYSTEMS DESIGN Digital Systems Design Overwiev IAY0600 Course Labs` Organization XILINX ISE Design Suite Overwiev Dmitri Mihhailov Tallinn University of Technology

2 Digital Systems Design Implementation possibilities:  Application-specific integrated circuits (ASICs)  Programmable logic devices (CPLDs, FPGAs)  Processor  General purpose processors  Special purpose processors (DSP, GPU) Digital Systems Design is a trade-off:  Time-to-market  Cost  Silicon Area  Performance  Power consumption  Development Complexity

3 Application-specific integrated circuits ASIC is an integrated circuit that is specifically designed for certain application ASIC development flow:  Design  Verification  Fabrication  Packaging  Testing  Refabrication (errors, change in specification)  Software development

4 ASIC design technolgies Full Custom Gate Array Standard Cell Structured

5 Full Custom ASICs [1]  development from scratch  complete control over each layer  may include analog circuitry  special tools  highly complex and time consuming  allows highest optimization [1] custom_design

6 Gate array ASICs [2]  basic cells are premanufactured  only connections are needed  fabrication is done much faster and cheaper  standard tools and component libraries  lower density and performance  almost obsolete [2] Clive Maxfiel, Bebop to the Boolean Boogie. An Unconventional Guide to Electronics, 2nd Edition, Newnes, 2003

7 Standard cells ASICs [2]  standard cells are predesigned  finding optimal placement and routing is needed  full fabrication cycle  standard tools and component libraries  close to optimal  higher abstraction  IP cores  dominant technique [2] Clive Maxfiel, Bebop to the Boolean Boogie. An Unconventional Guide to Electronics, 2nd Edition, Newnes, 2003

8 Structured ASICs [3]  premanufactured base tiles/modules and RAMs, PLLs, clock trees, etc.  only connections are needed  fabrication is done much faster and cheaper  standard tools and component libraries  lower performance [3] Clive Maxfield. (2004) The Design Warrior's Guide to FPGAs, Academic Press, Inc. Orlando, FL, USA

9 Programmable logic device technolgies Complex Programmable Logic Devices (CPLDs) Field Programmable Gate Arrays (FPGAs) Simple Programmable Logic Devices (SPLDs)  PROM  PLA  PAL  etc.

10 Simple programmable logic device [3] [3] Clive Maxfield. (2004) The Design Warrior's Guide to FPGAs, Academic Press, Inc. Orlando, FL, USA Programmable logic array (PLA)  allows Sum of Products (SoP) implementation

11 Complex programmable logic device [4] [4] CoolRunner-II CPLD Family Data Sheet, DS090 (v3.1). September 11, 2008

12 Field-programmable gate array (1) FPGA is an integrated circuit that contains (re)configurable blocks of logic and (re)configurable interconnect. FPGA development flow:  Design  Verification (functional and hardware)  Redesign (errors, change in specification)  Software development Field-programmable means that (re)configuration can be done “in field” (even when device is already deployed)

13 Conceptual structure of an FPGA [5] [5] Chu, P. P. (2008) References, in FPGA Prototyping by VHDL Examples: Xilinx Spartan™-3 Version, John Wiley & Sons, Inc., Hoboken, NJ, USA

14 Three-input LUT-based logic cell [5] [5] Chu, P. P. (2008) References, in FPGA Prototyping by VHDL Examples: Xilinx Spartan™-3 Version, John Wiley & Sons, Inc., Hoboken, NJ, USA

15 Three-input LookUp Table (LUT) (1) [3] [3] Clive Maxfield. (2004) The Design Warrior's Guide to FPGAs, Academic Press, Inc. Orlando, FL, USA

16 Three-input LookUp Table (LUT) (2)

17 Three-input LookUp Table (LUT) (3)  write out Sum of Products (SoP) and product of Sums (PoS) representations

18 Field-programmable gate array (2) The main FPGA manufacturers:  Xilinx and Altera ??? (acquired by Intel)  Lattice, Microsemi (Actel), SiliconBlue, Achronix, QuickLogic, Tabula (approx. 20% of the market) Other FPGA components:  Dedicated carry logic and interconnect  Embedded RAMs (dual-port)  DSP blocks (dedicated adder, multipliers, etc.)  Processor cores  Dedicated clock tree and clock managers  Configurable GPIOs (voltage, impedance)  Gigabit transceivers  SRAM-based configuration (also FLASH-based)

19 ASICs vs FPGAs FPGA can be used to prototype ASIC  Time-to-market  Cost  Silicon Area  Performance  Power consumption  Development Complexity Faster for FPGA (no fabrication required) FPGA is cheaper for low-volume production ASICs need less for the same functionality ASICs generally offer better performance ASICs are more power efficient FPGAs are easier to design with

20 FPGAs vs Processors On the whole Processors tend to be a better option (if applicable)  Cost, Silicon Area, Power consumption  Time-to-market  Performance  Development Complexity Comparable Faster for Processors (only software is required) FPGAs outperform only in case of massive parallelism Processors are easier to design with

21 Designing Digital Systems Digital Design entry:  Schematic  HDLs (VHDL, Verilog, SystemVerilog)  High-level synthesis (C, C++, SystemC) Digital Design with HDLs:  Logic gate level  Register Transfer Level (RTL)  Use synthesizable SUBSET of HDL Designer should “help” the tool:  Consider the technology  Employ recommended coding style  Be as specific and clear as possible

22 Designing with FPGAs FPGAs are likely to benefit from logic redundancy-based techniques:  pipelining, one-hot FSM state encoding, resource duplication instead of sharing, etc. Logic gate-based optimization are likely to be inefficient for FPGAs  LUTs are used to implement combinational logic Asynchronous design is generally not suited for FPGAs  avoid use of latches, asynchronous structures, combinational loops, etc.

IAY0600 DIGITAL SYSTEMS DESIGN IAY0600 DIGITAL SYSTEMS DESIGN LABS Dmitri Mihhailov Tallinn University of Technology

24 Digital Systems Design Labs Staff Lecturer:  Alexander Sudnitson (associate professor)   ICT-503 ( ) Lab Assistant:  Dmitri Mihhailov (research scientist)   ICT-505 (no phone) Technical Assistant:  Artjem Rjabov (early stage research scientist)   ICT-512 ( )

25 Lab Time:  GROUP A  Wednesdays 16: :30 (primary time)  ICT-502AB  GROUP B  Wednesdays 17: :15 (reserve time)  ICT-405 IAY0600 Digital Systems Design Labs (1) Lab Room:  ICT-502AB (~ 30 working places)  ICT-405 (15 working places)  Lab PCs require the same password that is used to access other computers in TUT network

26 The lab course consists of 10 labs:  Tutorial (essentially not a lab)  Set of compulsory labs (4 labs)  Set of optional labs (5 labs) IAY0600 Digital Systems Design Labs (2) Lab Course webpage:   IAY0600l Digital Systems Design (WORKSHOPS)  The target lab course:  LABS SET I (Xilinx FPGA-based)

27 Optional labs:  Form the advanced core of the course  NOT REQUIRED to pass the course  Increase the final grade Overview of the Lab Types Compulsory labs:  Form the basic core of the course  MUST be completed within deadline  Yield minimum positive final grade  Allow possibility to attend the exam Tutorials:  Introduce the working flow of design tools  Optional

28 Optional labs (+60 points in total):  Lab 6 (Finite State Machine) +20 pts.  Lab 7 (Greatest Common Divisor) +10 pts.  Lab 8 (Linear Feedback Shift Register) +10 pts.  Lab 9 (Creeping Line) +10 pts.  Lab 10 (RISC Processor) +10 pts. LABS SET I (Xilinx FPGA-based) Lab 1 (Tutorials) Compulsory labs (+30 points):  Lab 2 (Comparator)  Lab 3 (Adder)  Lab 4 (Parameterizable Adder)  Lab 5 (Shift Register)

29 List of General Lab Requirements General lab requirements (NOT final):  The deadline is 16 th week (all labs)  One extra DEFENSE ONLY session may be added during the first week of examination session  Labs are done either INDIVIDUALLY, or in teams of TWO students  Labs are passed in the same order as they are listed on the webpage  Lab manuals DO NOT feature all the necessary information for solving the task  Some lab manuals feature TASK description and EXAMPLE solution of a similar task

30 Step 3 (Defense, INDIVIDUAL):  Book a slot for defense during lab session  Be ready to answer ANY questions How to Pass a Lab Step 1 (Visual Demonstration):  Working prototype is examined for functional correctness during lab session Step 2 (Report, INDIVIDUAL):  Submit the following to (cc:  Lab report (PDF)  Source files (*.vhd, *.sch, *.ucf)  Wait for acknowledgment of acceptance

31 How to Write a Report Reports are written in FREE form The goals of lab report:  Document the workflow  Describe the results and their significance  Demonstrate writer’s comprehension List of topics to cover in the report:  Introduction  Background  Workflow  Results and discussion  Conclusion (including feedback)  References and appendices

32 List of General Report Requirements General report requirements (NOT final):  Lab report MUST feature things that are specifically required to be included in the task  All objects in the text MUST be numbered, labeled and referenced  All concepts, statements, results MUST be explicitly described in verbal form within text  Complete source codes MUST NOT be part of the report (even in appendices)  Functional simulation MUST always be performed and described

33 Design Tools and Equipment in the Lab FPGA boards:  Digilent Nexys-3 (Xilinx Spartan-6 FPGA)  used for labs 2-5  Digilent ZedBoard (Xilinx Zynq-7020 FPGA)  used for labs 5-10  replaced with Digilent Nexys-4 (Xilinx Artix-7 FPGA ) Xilinx Design Software:  ISE Design Suite (7-series and older)  System Edition (in the lab )  WebPACK Edition (free)  Vivado Design Suite (7-Series and newer)  System Edition (in the lab)  WebPACK Edition (free)

IAY0600 DIGITAL SYSTEMS DESIGN XILINX ISE DESIGN SUITE OVERVIEW Dmitri Mihhailov Tallinn University of Technology

35 Xilinx ISE Design Suite Project Navigator GUI:  Sources window (top left)  Processes window (middle left)  Workspace window (top right)  Console Message window (bottom) Project Navigator tools:  PlanAhead  ISim  XPower Analyzer  iMPACT Project Navigator is graphical interface for project and design management

36 Project Navigator GUI

37 Project Navigator Sources Window 1 Design views  Implementation  Simulation 2 Top-level module marker 1 2

38 Project Navigator Processes Window (1) Main design processes:  Design Summary  Design Utilities  User Constraints

39 UCF Pin Assignment in Text Editor Format of Pin Assignment in UCF: NET “design_pin_name” LOC = FPGA_pin_number;

40 Project Navigator Processes Window (2) Synthesize process:  Performs logic synthesis (HDL constructs are transformed to generic digital components)  View RTL and Technology Schematics  Check Syntax  Generate Post-Synthesis Simulation Model

41 Project Navigator Processes Window (3) Implement Design processes:  Translate - creates a single design netlist  Map - maps logic to FPGA components  PaR - derives physical layout within FPGA  Generate Post-... Simulation Model  Timing and Power Analysis

42 Xilinx XPower Analyzer XPower Analyzer tool overview:  Report thermal information  Report static and dynamic power consumption  Identify areas where power can be reduced

43 Project Navigator Processes Window (4) Generate Programming file process:  Set FPGA start-up clock to JTAG Clock Configure target device process:  iMPACT tool Analyze Design process:  ChipScope tool

44 Xilinx iMPACT Configuration Tool Configure FPGA device:  Select Boundary Scan iMPACT flow  Initialize JTAG chain  Set appropriate *.bit file to FPGA (skip SPI/BPI)  Program FPGA device

45 Project Navigator Processes Window (5) Simulation process:  ISim tool Simulation view:  Simulate design at different steps in design flow

46 Xilinx ISim Simulator Tool 1 ISim Simulator windows:  Simulation Objects (no variables)  Instances and Processes  Waveform 2 Re-launch button 2 1

47 Project Navigator Workspace Window 1 Language Templates 2 Float Window 1 2

48 Project Navigator Console Window Console views:  Console (shows all messages)  Errors (shows only error messages)  Warnings (shows only warning messages)

49 Nexys-3 FPGA Board (1) [6] Nexys-3 FPGA board features:  Xilinx Spartan-6 XC6LX16-CS324-3  Total of 48Mbytes of external memory  10/100 Ethernet port  micro USB port for power and programming  micro USB UART port  Type-A USB host port  VGA port  Four Pmod and one VHDC GPIO connectors  Eight slide switches, five push buttons and eight LEDs, four-digit seven-segment display  100MHz fixed-frequency oscillator [6] Nexys 3 FPGA Board Reference Manual, Digilent Inc., April 11, 2016.

50 Nexys-3 FPGA Board (2) [6] [6] Nexys 3 FPGA Board Reference Manual, Digilent Inc., April 11, 2016.