Lab_6_--_2-out-of-5_to_bcd_code_converter_with_display.docx

FacultyMember: . Semester:

Engr Arshad Nazir

Date: 3rd April, 2018

2nd

Section: BESE-8A

EE221 – Digital Logic Design

Lab7: Part (a): Design of 2-out-of-5 to BCD Code Converter with Display Part (b): Gate-level Modeling in Verilog

S. No.

Student Name

Reg. No.

S1

Muhammad Shaharyar

211690

S2

Muhammad Usama

212622

S3

Taimoor Khan Mahsud

212573

Total Marks

S4 Method: Viva, Lab report and instructor observation during lab session. Outcome Assessed:

Group No. 7

a. Ability to conduct experiments, as well as to analyze and interpret data (P). b. Ability to function in a team (A). c. Ability to use the techniques, skills and modern engineering tools necessary for engineering practice (P). Does not meet Marks Exceeds expectation Meets expectation Performance expectation (10--8)/(5--4) (7--5)/(3) S1 S2 S3 (4--1)/(2--1) 1.Realization Of Experiment [c] 10

2. Teamwork [b] 5 3.Conducting Experiment [a] 5

4. Laboratory Safety Rules [a] 5 5. Data Collection[a] 10

Selects relevant equipment to the experiment, develops setup diagrams of equipment connections or wiring. Actively engages and cooperateswith other group members in an effective manner. Does proper calibration of equipment, carefully examines equipment and wiring components, and ensures smooth operation and process. Respectfully and carefully observes safety rules and procedures. Plans data collection to achieve experimental objectives, and conducts an orderlyand a complete data collection.

EE-221: Digital Logic Design

Needs guidance to select relevant equipment to the experiment and to develop equipment connection or wiringdiagrams.

Incapable ofselecting relevant equipment to conduct the experiment, equipment connection or wiring diagrams are unrecognizable.

Cooperates with other group members in a reasonable manner.

Distracts or discourages other group members from conducting the experiment.

Calibrates equipment, examines equipmentand wiring of components and operates theequipment with minorerror. Observes safety rules and procedures Withminor deviation. Plans data collectionto achieve experimental objectives, and collects complete data with minor error.

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Unable to calibrateappropriate equipmentand wiring, and equipment operation is substantially wrong. Disregards safety rules and procedures. Does not know how to Plan data collection toachieve experimental goals; data collected is incomplete and contain errors.

S4

Lab7: Part (a): Design of 2-out-of-5 to BCD Code Converter with Display This Lab Activity has been designed to familiarize the student with design and working of a 2-outof-5 to BCD Code Converter with numeric Display circuit. Psychomotor Level P-4 Objectives:    

Simplification of output Boolean functions using Five-Variable map from truth table. Design of Code Converter block using Two-Level NAND gates. System integration with BCD-to-Seven-Segment Decoder and Numeric readout for decimal display. Understand the difference between common cathode and common anode displays

Lab Instructions This lab activity comprises three parts, namely Pre-lab, Lab tasks, and Post-Lab Viva session.  The lab report will be uploaded on LMS three days before scheduled lab date. The students will get hard copy of lab report, complete the Pre-lab task before coming to the lab and deposit it with teacher/lab engineer for necessary evaluation.  The students will start lab task and demonstrate design steps separately for stepwise evaluation (course instructor/lab engineer will sign each step after ascertaining functional verification)  Remember that a neat logic diagram with pins numbered coupled with nicely patched circuit will simplify trouble-shooting process. 

     

After the lab, students are expected to unwire the circuit and deposit back components before leaving. The Total duration for the lab is 3 hrs. The students are expected to complete lab within specified time. A lab with in-complete lab tasks will not be accepted. The students will complete lab task and submit complete report to Lab Engineer before leaving lab. There are related questions at the end of this activity. Give complete answers. This lab is OBE compliant.

EE-221: Digital Logic Design

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Pre-Lab Tasks: 1.

What do you mean by non-weighted codes? Give any two examples. (1 Mark) Answer: The codes which have no positional weights are called non-weighted codes. In other words, the codes which are not given any weights, such as: Gray code, 2 out of 5 code, XS-3 code etc. In gray code 3 is represented as 0010 then actually it would have been 0010 it represents 3.

2.

What are de-generate forms? List any five. What are the applications of these forms in digital design? (2 Marks) Answer: In a two level circuit those combinations which are reduced to a single operation are called degenerate forms. 1. AND-AND 2. OR-OR 3. AND-NAND 4. OR-NOR 5. NAND-OR

3.

7-Segment LED Displays are commonly used for displaying decimal Numbers (0 to 9). It can also be used for displaying alphabets. A 7-Segment LED Displays essentially consist of 7 LEDs configured as shown below to display numbers. It comes in two configurations. Common Cathode and Common Anode. Draw the diagram showing connections to drivers and power source and ground for both configurations and highlight differences between the two. Also give signal logic level required to light up the LEDs in the segment in each configuration: (2 Marks)

EE-221: Digital Logic Design

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4.

Complete the following table. Dec

(3 Marks)

A

Inputs (2-out-of-5) B C D

W

Output(BCD) x y

E

z

0

1

1

0

0

0

0

0

0

0

1

0

0

0

1

1

0

0

0

1

2

0

0

1

0

1

0

0

1

0

3

0

0

1

1

0

0

0

1

1

4

0

1

0

0

1

0

1

0

0

5

0

1

0

1

0

0

1

0

1

6

0

1

1

0

0

0

1

1

0

7

1

0

0

0

1

0

1

1

1

8

1

0

0

1

0

1

0

0

0

9

1

0

1

0

0

1

0

0

1

∑d( 5.

) Simplify the output functions w, x, y, and z using map method. Try to take maximum advantage of don’t care conditions. (5 Marks) W= DE + CE = [(DE)’.(CE)’]’ X= AE + BE + A’DE’ = [(AE)’.(BE)’.(A’DE’)’]’ Y= AB’ + BE = [(AB’)’.(BE)]’ Z= B’D + AB + BE = [(B’D)’.(AB)’.(BE)]’

EE-221: Digital Logic Design

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Lab Tasks: Lab Task 1 6.

Give complete schematics for your design including 2-out-of-5 to BCD Code Converter block, BCD-to-Seven-Segment driver IC and read out. A Schematic is a logic diagram with pin numbering and IC Labeling on each gate. (3 Marks)

EE-221: Digital Logic Design

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7.

Implement the above circuit in hardware using minimum number of NAND gates at TwoLevel and show the results to Teacher/Lab-Instructor. (10 Marks)

8.

Mention which configuration of 7-Segment Display did you use in Lab? If you were to use the other configuration what change would you need in your circuit? (1 Mark) Answer: We used common anode display for the output as the values a, b, c… were already in complemented form. If we used the common cathode display, it would be needed to flip the 1’s and 0’s of the BCD to convert the complemented values back to the original values.

Part (b): Gate-level Modeling in Verilog Lab Task 2: EE-221: Digital Logic Design

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9.

Design and simulate the gate-level model of the circuit you have patched. Give the code in the space provided. (8 marks)

Code:

Output:

EE-221: Digital Logic Design

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Observations/Comments: It took us a lot of time to complete the lab as the decoder IC was faulty and after long time we came to know that it was not working. W could also be expressed as ((A’B’E)’). If we used this expression we din’t need to use C and the circuit could be implemented using four switches only.

EE-221: Digital Logic Design

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