1. Programmable Logic DevicesLecture #1 Digital Fundamentals with VHDL by Thomas L. Floyd

2. Analog vs. Digital Analog: Infinite values are measurable in both time and temperature. Digital: Bothe time and temperature are quantized.

3. The Digital Advantage • Data Processing • Data Transmission • Data Storage

4. Digital and Analog electronics together

5. Binary Digits Positive Logic HIGH = 1 Low = 0 Or Negative logic High =0 Low =1

6. Digital Waveform

7. Period and Frequency Frequency (f) is measure in cycles per second or Hertz (Hz) Period (T) is measured in seconds f = 1/T T = 1/f

8. Pulse Width and Duty Cycle Duty cycle = (tw/T)100%

9. Data Transmission

10. Basic logic operations and symbols

11. The NOT operation

12. The AND operation

13. The OR operation

14. Basic Logic Functions • Comparison Function • Arithmetic Functions • Code conversion function • Encoding function • Decoding function • Data selection function • Data storage function • Counting function

15. Basic Logic Functions Comparison Function

16. Basic Logic Functions Arithmetic Functions

17. Basic Logic Functions Encoding Function

18. Basic Logic Functions Decoding Function

19. Basic Logic Functions Data Selection Function

20. Basic Logic Functions Storage Function: Flip-flops, Registers, Memory Elements 4-bit Shift Register

21. Basic Logic Functions Storage Function: Flip-flops, Registers, Memory Elements 4-bit Parallel Shift Register

22. Basic Logic Functions Counting Function

23. Basic Logic Functions

24. Fix-Function Integrated Circuits

25. Fix-Function Integrated Circuits Plastic Leaded Chip Carrier Leadless Ceramic Chip Carrier

26. Pin numbering

27. Integrated Circuit Complexity Classifications SSI Small-Scale Integration describes fixed-function IC’s that have up to twelve equivalent gate circuits on a single chip, and the include basic gates and flip-flops. MSI Medium-Scale Integration describes integrated circuits tat have from 12 to 99 equivalent gates on a chip. They include logic functions such as encoders, decoders, counters, registers, multiplexers, arithmetic circuits, small memories, and others. LSI Large-Scale Integration is a classification of ICs with complexities of 100 to 9999 equivalent gates per chip. VLSI Very Large-Scale Integration describes integrated circuits with complexities of 10,000 to 99,999 equivalent gates per chip. ULSI Ultra Large-Scale Integration describes very large memories, larger microprocessors, and larger single-chip computers. Complexities of 100,000 equivalent gates and greater are classified as ULSI.

28. Integrated Circuit Technologies • TTL • ECL • CMOS • NMOS • SSI and MSI use TTL or CMOS • VLSI and ULSI use CMOS or NMOS

29. Programmable Logic Devices (PLDs) Programmable logic devices can replace fix-function logic - the major advantage is that the logic function of the PLD can be changed without rewiring. SPLDs (Simple Programmable Logic Devices) CPLDs (Complex Programmable Logic Devices)

30. Types of SPLDs • PAL (Programmable Array Logic) • GAL (Generic Array Logic) • PLA (Programmable Logic Array) • PROM (Programmable Read-only Memory)

31. Types of CPLDs • CPLDs are made using 2 to 64 SPLDs using 44-pins to over 200-pins

32. Field Programmable Gate Arrays Field Programmable Gate Arrays (FPGA) consist of an array of 64 to thousands of logic groups called “logic blocks” There are two types of logic blocks fine-grained FPGAs with smaller logic blocks course-grained FPGAs with large logic blocks

33. PLD programming • Schematic Entry –logic diagram • Text-Based Entry using hardware description language(HDL)

34. PLDs versus Fixed-function Logic • Differences between fixed-function logic and programmable logic • Advantages of programmable logic over fixed-function logic • Implementing fixed-function logic • Implementing programmable logic

35. To implement a system using fixed-function logic • Design system • Select devices • Layout printed circuit board • Manufacture printed circuit board • Install ICs on the printed circuit board • Test the system

36. Fixed-function Approach

37. Advantages of Programmable Logic Approach • Less time required to implement • Less space required on printed circuit board • Quicker design change implementation

38. To implement a system using a PLD • Define the system requirements • Install PLD development software on the computer • Write the program describing the hardware • Enter the program and run simulation software to test the system • Run the software to physically implement the system design in the PLD

39. Basic programming set up for a PLD

40. Programming • Basic Software Concepts • Algorithms (sequential steps) • Programming Languages (sequential steps) • High-level • Assembly • Machine • VHDL • Very high speed integrated circuit Hardware Description Language (describes hardware layout-not a sequential operation!)

41. Hardware Descriptive Languages • VHDL- IEEE standard language • Verilog – IEEE standard language • AHDL – proprietary language • ABEL – proprietary language • CUPL – proprietary language

42. History of VHDL • Initiated by Department of Defense in 1981 • Rights to VHDL transferred to IEEE and first version published in 1987 • Revision published in 1993 as IEEE standard 1076-1993

43. Using VHDL to program a digital logic design • Define and document what the program is going to do • Determine a solution and document how the task is to be accomplished • Create and document the program • Test and debug the program and document any revisions • Implement the design

44. Development Software • Development Software Supplied by Manufacturer • Altera • Lattice • Xilinx • Cypress

45. VHDL overview • Entity and architecture- minimum requirement of program • Define port • Structural approach • Data flow approach • Behavioral approach

46. Entities-TheExteriorDescription • Describes a logic function as viewed from the outside • Defines the inputs and outputs, called a port • Defines the data type • Describes external aspects of the logic function

47. Architecture – The Interior Description • Describes the internal operation of the logic function in one of three ways • Structural description • Data flow description • Behavioral description

48. Architecture

49. Structural or Data Flow approach • Structural approach • Described in terms of basic logic gates • and their interconnections (like Boolean algebra) • Data flow approach • Described by how signals flow through the logic gates (like Truth Tables or Next State Tables) • Both approaches deal with the internal details of the logic function

50. Behavioral approach • Describes the logic function in terms of what happens on the outputs in response to the inputs (like State Diagram) • Used for complex designs