**KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS**

DEPARTMENT OF SYSTEMS ENGINEERING

**SE311**

**DIGITAL SYSTEMS DESIGN**

**INSTRUCTOR :** Dr. Moustafa Elshafei

Binary arithmetic. Boolean algebra. Boolean functions and their simplification. Implementation of Boolean functions using logic gates, SSI, MSI, and LSI chips. Analysis and design of combinational circuits. Sequential logic: flip-flops, counters and registers. Analysis and design of sequential circuits. Basic elements of digital computers: register transfer, micro operations, instruction codes, processor organization, arithmetic and logic unit.

TOPIC WEEKS

1- BINARY SYSTEMS : 1

2- BOOLEAN ALGEBRA AND LOGIC GATES 2

3- SIMPLIFICATION OF BOOLEAN FUNCTIONS 2

4- COMBINATIONAL LOGIC 2

5- MSI AND LSI COMPONENTS 2

6- SYNCHRONOUS SEQUENTIAL CIRCUITS 3

7- REGISTERS COUNTERS AND MEMORIES 2

9- DIGITAL INTEGRATED CITCUITS (lab)

LAB and PROJECT 30 %

FINAL 30 %

Majors 20 %

QUIZES 10 %

ATTENDANCE and ASSIGNMENTS 10 %

1- Mano, 1-17, 1-19, 1-27, 1-29, 1-34

2- Mano, 2-6, 2-7, 2-8, 2-11, 2-17 (a,b), 2-21

3- Mano, 3-2(c), 3-3(c), 3-5(c), 3-8(c), 3-20, 3-23.

4-Mano, 4-1, 4-3, 4-4, 4-7, 4-16, 4-18, 4-28.

5- Mano, 5-1, 5-2, 5-10, 5-11, 5-17, 5-20, 5-27.

6- Mano, 6-6, 6-7, 6-8, 6-20.

**Students Remarks**

1- The text book is in general easy to read and to follow. However, the book lacks examples. Although it has plenty of exercises, the majority of them are difficult, and/or take too much time to solve.

**Instructor Remarks.**

1- I introduced the use of Computer Aided Design package " Electronic workbench". This software helps students to draw and analyze the logic circuits, observe the timing and waveforms in a virtual oscilloscope, understand the function of logic analyzers, and simulate and debug their circuit design. Students were very excited because it helps them to analyze and solve more complex problems in much shorter time.

2- I also introduced small application projects. Each project was executed by 3-4 students. These projects enhanced their team work attitude and developed their innovation and creativity skills. Students demonstrated their ability to execute small design projects from verbal description to design and testing. Students built 5 working projects :

1- Irrigation Timer

2- Digital clock with start and stop timed actions.

3- Stepper motor controller.

4- Washing machine controller.

5- Prayer counter.

6- Electronic game

1- Timer for irrigation

Design a timer which automatically turns on & off water supply to a garden on a regular intervals e.g., 4, 8, 12,24,48, or 72 hours. The ON-TIME can be selected e.g., 10, 20,30,45,60,90,or 120 minutes.

The device should be provided with a mains on-off switch, a reset switch, and an indicator LED when the water is on.

Use 12 volt DC. Assume the timer has an output relay which operates at 12 volts, requires 80 mA, and 2 Amp contacts.

(Hint use 555 timers)

**2- LARGE Digital clock**

We would like to design a jumbo digital clock. The 7-segment displays will constructed from array of lamps under a plastic cover. The frequency source is the 60 Hz from the main supply. Use a step down transformer to get 3 volts Ac. and rectify it by a single diode, and clamp it to 5.o Volts. This will give you approximately a rectangular 60 Hz. Now pass it into a decade (BCD counter) to get a 6 Hz frequency. Again pass it through a divide by 6 counter you get 1 Hz. proceed this way to get Minutes and hours. as shown in the figure below. The output from the BCD to 7-segment decoders should actually be buffered and used to derive a segment relay. This relay in turn will turn the lamps of the corresponding segment on-off.

3- Stepper Motor Deriver

Design a Stepper motor deriver circuit that would allow change of speed, change of direction, and holding of s stepper mottor,

Use 555 as a variable frequency generator from 0.25 - 500 Hz by a potentiometer, an up-down counter, and a 2:4 decoder. The coils of the stepper motor require 500 mA @ 5 volts.

4- Electronic game

The player should try to pass the ring through the twisted wire as fast as possible without touching the wire. Counter A counts the number of touches, and Timer B indicates the time to finish. The score is a function of the indication of the counter and the timer.

5- Washing machine

The over all washing cycle consists of 8 periods. During each period certain action takes place. The actions are determined by turning on or off the inlet valve, the drain valve, the heater, the low speed agitation motor, and the fast spin motor. The schedule of these actions is shown below

A | B | C | D | E | F | G | |

spin motor | |||||||

ag. motor | |||||||

heater | |||||||

drain valve | |||||||

inlet valve |

For simplicity you may take all the periods A,B,.....G to be equal. However you they can be made different at the expense of increase in the complexity of the logic circuit.