Aims

The aims of the course are to:

• Familiarise students with combinational and sequential digital logic circuits, and the analogue-digital interface,
• Familiarise students with the hardware and basic operation of microprocessors, memory and the associated electronic circuits which are required to build microprocessor-based systems.
• Teach the engineering relevance and application of digital and microprocessor-based systems, give students the ability to design simple systems of this kind, and understand microprocessor operation at the assembly-code level.

Objectives

As specific objectives, by the end of the course students should be able to:

• Know the nomenclature and the representation of basic gates and digital electronic components (including shift registers, counters, latches, RAM and ROM ICs)
• Understand Boolean algebra, and be able to convert verbal descriptions of requirements into Boolean notation
• Understand the need to simplify logic functions or rearrange them to use specific gate types; be able to use Boolean algebra and Karnaugh maps (for up to 4 variables) to achieve these tasks; be able to use "don't care states" in K-maps.
• Know about logic "families", the electronic circuit implementation of logic gates, and the resulting engineering issues (voltage thresholds, noise margin, finite rise time and delay)
• Know about Schmitt inputs; understand static hazards and be able to detect them using K-maps and correct them
• Be familiar with standard number codes for representing data (two's complement notation, sign+magnitude, one's complement, Gray code, ASCII); be able to convert between binary, hex, octal and decimal.
• Understand the operation of logic circuits for addition, negation and subtraction of binary integers
• Be familiar with examples of elementary VHDL and understand why it is useful
• Understand the distinction between combinational and sequential logic and the role of sequential logic; be familiar with unclocked and clocked S-R latches, D-type and JK flip-flops.
• Understand the operation and use of synchronous and asynchronous counters and shift registers.
• Understand state diagrams and their role in sequential circuit design; be able to convert a problem statement into a state diagram; be able to convert a state diagram into a circuit design based on JK flip-flops
• Understand unused states, and be able to guard against errors due to them. Be able to carry out the complete design process, from problem statement to circuit design.
• Understand the operation of weighted resistor and R-2R ladder DAC circuits
• Understand the operation of Full Adder and Ripple Carry Circuits
• Understand ROM and RAM memory circuits, the function of their control, address and data pins, and their use in digital (including microprocessor) systems
• Understand the use of tri-state outputs and busses.
• Understand and be able to design address decoders, including partial address decoders for simple systems.
• Be familiar with the system architecture of a typical PIC microprocessor system, including the ALU, memory, I/O;understand how it can be used in practical applications.
• Be familiar with the internal architecture of a typical PIC microprocessor (the PIC12F629/675) and its instruction set, and understand how instruction execution occurs.
• Understand the features of typical instruction sets,and be able to use the full instruction set (from the tables in the electrical data book).
• Be able to write simple programs in assembler mnemonics, including conditional branches, and calculate their execution times in clock cycles; know about the relationship of higher level languages to assembly level code.
• Understand (in outline only) stacks, subroutines and the hardware reset function.

Content

Digital Fundamentals and Combinational Logic

• Introduction, revision of simple logic gates, overview of logic circuit families. [1] Ch 3, [3] 392-399, [4] 12
• Circuits for inverters and basic logic gates in NMOS and CMOS. [3] 409-410, [5] Ch 2,
• Boolean algebra and its application to combinational logic. Karnaugh maps for function minimisation. [3] 436-446, [4] 39-60, [5] Ch 3,
• Gate delays, timing diagrams, hazards. [4] 391-398
• Introduction to VHDL.

Sequential Logic and its Applications

• Number codes, for example, hexadecimal, BCD, ASCII. 2's complement. [1] Ch 2, [2] Ch 3, [3] 430-435, [4] Ch 10, [6] Ch 3,
• RS and JK flip-flops, latches and simple counters.[3] 412-419, [5] Ch 4,
• Synchronous and asynchronous circuits, counters and shift registers. Serial communication. [3] 446-452, [6] Ch 5
• State diagrams and design methods for a sequencer. [4] Ch 4, [5] Ch 6
• D to A techniques. Weighted resistor and R-2R ladder networks. Schmitt trigger inputs. [3] 522-523
• Logic circuits for arithmetic functions.[3] 442, [4] 17

Introduction to Microprocessors

• Introduction to the architecture of a simple microprocessor. [1] Ch 1,5, [2] 1-9, [4] Ch 1 and Ch 5, [7] 10-13
• Memory circuits, RAM and ROM. Address decoding, definitions of read/write and chip select signals. [2] Ch 12, [3] 455-460, [4] Ch 6, [6] Ch 2
• PIC Microprocessor programming. Programme Development, Registers. [1] Ch 7, Ch 8
• Programming examples based on PIC12F629/675 instruction set. Addressing modes. Implementation using simple machine code. Assembly code and higher level languages. [1] Ch 8,9

REFERENCES

1) BATES, M. PIC MICROCONTROLLERS: AN INTRODUCTION TO MICROELECTRONICS
(2) DOWSING, R.D., WOODHAMS, F.W.D. & MARSHALL, I. COMPUTERS FROM LOGIC TO ARCHITECTURE
(3) FLOYD, T.L. DIGITAL FUNDAMENTALS
(4) GIBSON, J.R. ELECTRONIC LOGIC CIRCUITS
(5) SMITH, R.J. & DORF, R.C. CIRCUITS, DEVICES AND SYSTEMS
(6) TINDER, R.F. ENGINEERING DIGITAL DESIGN

This syllabus contributes to the following areas of the UK-SPEC standard:

Toggle display of UK-SPEC areas.

 
Last modified: 29/07/2022 09:33