UNISA
UNIVERSITY OF SOUTH AFRICA
Digital Systems II
(DSY2602)
Practical Tutorial
Compiled by: Dr. M.E. Migabo
Lecturer: Mrs. I.M. Masopoga
Unisa
PO Box 392, UNISA, 0003
Copyright © Unisa 2021
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DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
TABLE OF CONTENTS
Practical Tutorial ..................................................................................................... 1
AUTHORISATION OF WORK FOR EXPERIMENTs ................................................. 3
DIGITAL SYSTEMS II ................................................................................................ 3
0. INTRODUCTION ................................................................................................. 4
1. components, SIMULATION TOOL AND lab equipments ..................................... 4
1.1.
LIST of Components......................................................................................... 4
1.2.
SIMULATION TOOL ......................................................................................... 5
1.3.
LAB EQUIPMENTS AND PERSONAL TOOLS ................................................ 6
2. PRACTICAL ASSIGNMENTS.............................................................................. 9
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
AUTHORISATION OF WORK FOR EXPERIMENTS
DIGITAL SYSTEMS II
Particulars of mentor:
Name:
Address:
Tel no: (h)
(w)
ECSA registration number:
Signature:
Particulars of ECSA member (if mentor is not an ECSA member):
Name:
Address:
Tel no: (h)
(w)
ECSA registration number:
Signature:
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
0. INTRODUCTION
This tutorial letter provides you with all the details about the practical component of
the DSY2602 module. It mainly provides you with the basic logistical information about
the required components, simulation tools and laboratory equipment, the brief
descriptions of practical experiments and the associated graduate attributes
evaluation rubrics.
1. COMPONENTS, SIMULATION TOOL AND LAB EQUIPMENTS
1.1.
LIST OF COMPONENTS
The following components are required to successfully complete the practical activities
of the DSY2602 module:
Part Number
Description
Quantity
74LS00N
NAND-Gate Quad 2-input
2
74LS04
Inverter HEX
1
74LS08
AND-Gate Quad 2-input
2
74HCT10
Triple Input NAND
1
74HCT11
Triple Input AND
1
74HCT20
Dual 4 Input NAND
1
74LS32
OR gate quad 2-input
1
74LS47
Decoder/driver BCD to 7-seg
2
74LS85
IC Comparator 4-bit DIP
1
74HCT112
Dual JK Negative-edge-triggered FF with preset
2
74HCT139
Dual 1 of 4 Decoder/Demultiplexer
1
74LS164
8-bit shift register
1
74LS373
8-bit Latch
2
NE555N-ST
Timer HA17555/NE555P-TI/LM555
1
CR25-100E-T
Resistor Carbon Film 1/4 W 5%
14
CR25-1K-T
Resistor Carbon Film 1/4 W 5%
4
CR25-6k8-T
Resistor 1/4 W 5%
1
10UF16VRSSR
10 uF Capacitor electrolytic 16 V
1
Capacitor multilayer 100 nF 50 V 5 mm
4
SA52-11EWA
Display 7-segment CA red ? cd 12,7 mm (TDSR1350)
2
BL-B5134
LED 5mm RD-DI rnd 12 mcd 25 mm
8
7805
3-Terminal Positive Voltage Regulator
1
PM9 Battery Connector
1
PM9 Battery
1
4 Way Dip Switch
1
Table 1: List of components
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
1.2.
SIMULATION TOOL
The simulation tool to use in this module is the National instruments (NI)’s Multisim
version 14.2 simulation platform. It can be downloaded at the following link:
https://www.ni.com/en-za/support/downloads/softwareproducts/download.multisim.html#312060
Figure 1: Screenshot of Multisim download page.
Create an account and/or login using your mylife email account or your company’s
email (gmail or yahoo and other personal emails will not work).
Below are couple of links to useful video tutorials on how to use Multisim:
https://www.youtube.com/watch?v=_KrOqpavFt4
https://www.youtube.com/watch?v=xrgxDccit8A
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PRACTICAL TUTORIAL
1.3.
LAB EQUIPMENTS AND PERSONAL TOOLS
In the laboratory at Florida campus, you will find the following laboratory equipments:
Equipment
Description
Links to video tutorials
Digital
This device is used to measure
https://youtu.be/4hARsKENyRk
Oscilloscope
signals in time domain and
https://youtu.be/bBxlZsNwrbU
characterize, measure, and
https://youtu.be/wN0NWZNU064
compare them in terms of
https://youtu.be/zOdT1ybZKpQ
amplitude, phase and
https://youtu.be/fxqCzPE3qOQ
frequency
Variable
DC Supplies regulated DC voltage
power Supply
selectable from 0 V to 30 V. It
has two channels that can be
used independently, in series to
provide higher voltage or in
parallel to supply more current
to the circuit.
Function
https://youtu.be/X5HsbQdKZuQ
Generator
https://youtu.be/duE2PSHzjBQ
Table 2: List of laboratory equipments
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
1.4.
TECHNICAL REPORT TEMPLATE
SSESSMENT
RECORDS
The following practical report is attached to serve as template and guide for the
structure of your technical reports for various experiments.
A practical report is an official document. This document must contain all the
information that gave rise to a project or assignment and the results obtained. The
purpose of documenting an experiment or project is so that it can be repeated or
continued by yourself or someone else if you become unavailable for any reason.
Documentation should thus not be considered as an afterthought but as an important
part of the preparation and procedure of the experiment or project. Documentation for
this course must be typed and must include the following:
1.4.1. THE COVER PAGE
The cover is a folder keeping all the sheets together. On the front of the cover the
following information must be written:
1. Subject:
2. Course: AND Specialization (LC, HC, CS, etc)
3. Title: (of experiment/project)
4. Student number:
5. Initials and Surname:
6. Practical group:
7. Date of completion:
1.4.2. REPORT
The report must be printed neatly on paper. The report consists out of the following:
a) TITLE
The name of the experiment or assignment.
b) AIM or PURPOSE
The aim of the experiment. This will include what you want to do OR attempt with
this experiment. This introductory part describes in steps what is to be observed or
achieved by the experiment or project.
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
c) EQUIPMENT AND COMPONENTS
A list consisting of:
•
all equipment that you are using.
•
all components that you are using.
d) DIAGRAMS
The following diagrams are required (where applicable):
•
Block diagram
•
Circuit diagram (or logic diagram)
•
Practical layout (is a planning of your circuit construction on the breadboard)
All diagrams must be fully labeled and drawn up to electrical standard.
e) METHOD (Procedure, Operating instructions to the user)
This section is a step-by-step procedure that must be followed by the user to
complete the experiment. The procedure to follow must be listed complete so that any
user can follow the steps and end with the same results.
f) FUNCTIONAL DESCRIPTION
The functional description describes the project with reference to the block diagram.
Only functions of each different block and their interaction are described.
g) SPECIFICATIONS
Specifications include the following data:
•
Physical size of the instrument
•
Supply voltage to the instrument
•
Power consumption of the instrument / circuit
•
Input signal levels (voltage - and current levels)
•
Output signal levels (voltage - and current levels)
h) PRINCIPLE OF OPERATION
The principle of operation is a detail description of the circuit diagram. Design
considerations and all calculations must be shown.
i) RESULTS, GRAPHS AND\OR TIMING DIAGRAMS AND ANSWERS TO
KNOWELEDGE QUESTIONS
All the output readings needed, must be taken (written down). From the results,
graphs and timing diagrams must be drawn on graph paper.
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PRACTICAL TUTORIAL
k) CONCLUSION
A complete analysis of what you observed from the circuit. This is also a summary
of the complete practical work done.
Suggestions of alternative applications can and must be listed.
l) BIBLIOGRAPHY
Title, publisher, and date of publication (from journal or book) and part where aid was
received, name of the person and workplace (company) of person who provided aid.
2. PRACTICAL ASSIGNMENTS
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
PRACTICAL EXPERIMENT 1.
IMPLEMENTATION AND ANALYSIS OF A LATCH AND J-K FLIP-FLOP CIRCUIT
Surname &
Initials:
1.1.
Student Number:
OBJECTIVE:
1. Construct a latch using NAND gates to supply a single pulse when triggered via
a switch at the input. This pulse can be used as a clock pulse for a gate circuit,
shift register or counter circuits. The advantage of using this latch is that it
eliminates contact bounce. (An explanation will be given in class
demonstrating how to use a piece of wire to create the SPDT switch since you
do not have one in your component pack).
2. Illustrate the operation of the JK Flip-Flip by means of a practical circuit.
1.2.
REFERENCE:
Manufacturer’s data sheets of NAND logic gate and the JK Flip Flop
1.3.
CIRCUIT DIAGRAM:
Figure 2: Experiment 1 Latch and J-K Flip Flop Circuit diagram
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
1.4.
COMPONENTS:
1 x IC
74LS00N (quad 2-input open-collector NAND gate)
2 x LED
5 mm LEDs (1 RED color and 1 GREEN in color)
1 x IC
74HCT112 Dual JK negative edge triggered Flip-Flop with
pre-set.
1.5.
Resistors
¼ Watt metal film through hole resistors
EQUIPMENT:
Development board
Logic Probe
Digital Multimeter
1.6.
KONOWLEDGE QUESTIONS (answer all in the report):
1. Explain what contact bounce is?
2. How does the latch in this experiment eliminate contact bounce?
3. Is the 𝑃𝑅𝐸𝑆𝐸𝑇 and 𝐶𝐿𝐸𝐴𝑅 pins on your J-K activated with a logic 0 or a logic
1?
4. When the 𝑆/𝑃𝑅𝐸𝑆𝐸𝑇 pin on the J-K flip-flop is grounded, what will the output Q
be equal to?
5. When the 𝐶𝐿𝐸𝐴𝑅 pin on the J-K flip-flop is grounded what will the output Q be
equal to?
6. Does the output Q for the experiment change on the positive or on the negative
edge of the clock pulse?
7. Simulate the operation of the circuit by using NI Multisim and fill up the following
truth table:
J
DIGITAL SYSTEMS II
K
CLK
PAGE 11
Q
𝑸
PRACTICAL TUTORIAL
8. Based on the circuit you have built, complete the truth table below:
J
K
CLK
Q
𝑸
9. Based on the circuit you have implemented, complete the timing waveform for
the inputs given as follows:
1.7.
MARKSHEET AND GRADUATE ATTRIBUTES ASSESSMENT
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
Practical Experiment 1 Rubric
Subject code
DSY2602
Date
Student number
Student surname and Initials
This experiment assesses competence in terms of graduate attribute 4 (GA4) which has to do with the
ability of the student to successfully conduct an investigation, an experiment and analyse the obtained
data in form of a technical report and knowledge questions in this particular case.
N.B: Points allocated under description column are the maximum points that can be obtained.
No
1
Mark = Point x Weight
Total (%) = sum of marks
Criteria
Description
Point
Construction
No circuit built by the student (0 point)
of logic circuit
Weight
5
Mark
Circuit is built by the student but it is not functional
(1 point)
Student only built correctly one of the latch subcircuit and the JK flip flop sub-circuit. (2 points)
Student built correctly both the latch sub-circuit and
the JK flip flop sub-circuit separately but fails to
integrate the two. (3 points)
Student built correctly both the latch sub-circuit, the
JK flip flop sub-circuit and correctly integrates the two
with the digital input circuit and the LED indication
output circuit. (4 points)
2
Simulation of
the circuit
Student performed no simulations of the circuit
(0 point)
5
The student performed a full simulation of the circuit
but only one of the latch sub-circuit as well as the JK
flip flop sub-circuit work perfectly fine in simulation.
(1 point)
The student performed a full simulation of the circuit
and both the latch sub-circuit as well as the JK flip
flop sub-circuit work perfectly fine in simulation .
(2 points)
3
Experiment
requirement
specifications
The latch and the JK flip flop sub-circuit do not both
works correctly (0 point)
15
One of the latch sub-circuit or the JK flip flop does not
work correctly. ( 1 point)
The flip-flop and the latch both work correctly
(2 points)
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PRACTICAL TUTORIAL
4
Neatness of
the circuit
Student's circuit is untidy. Connection wires are
connected in disorder.
(0 point)
Student's circuit is moderately neat.
3
(2 points)
Student's circuit is very neat. Connection wires and
components very well placed on the board.
(3 points)
5
Technical
Report and
Knowledge
Questions
Technical report not according to the provided
template and no question out of the 9 questions
correctly answered. (0 point)
1
Correct report template used, and knowledge
questions answered. (31 points): (1 point for correct
template used and per correct answer for questions
Q1 to Q6) (8 points per correct answer for questions
Q7 to Q9).
Total (%)
29
Assessor's
surname and
initials
Assessor's
Signature
Student's Signature
GRADUATE ATTRIBUTES (GAs) ASSESSMENT (Decision: Met, Not met)
GAs
Score (0-5)
=Total/20
Decision (Met if score 3 and higher, Not met
otherwise)
GA4
Overall Comment
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
PRACTICAL EXPERIMENT 2.
IMPLEMENTATION AND ANALYSIS OF AN ASTABLE 555 TIMER CIRCUIT
WITH MOD 10 COUNTER
Surname &
Student Number:
Initials:
2.1.
OBJECTIVE:
To design a mod 10 counter using JK Flip-Flops. The clock pulse for the counter
will be generated using a 555 timer as an astable multivibrator. The output must be
displayed on a seven-segment display.
2.2.
REFERENCE:
Manufacturer’s data sheets of the HA17555 or the NE555P-TI or the LM555
555 timer IC, the 74LS47 decoder and the 74HCT112 JK Flip Flop.
2.3.
IMPORTANT DESIGN FORMULA:
𝒇=
2.4.
2.5.
𝟏. 𝟒𝟒
(𝑹𝟏 + 𝟐𝑹𝟐 ) × 𝑪𝟏
DESIGN SPECIFICATIONS:
•
Frequency= 10 Hz
•
Duty Cycle=50%
•
C1=10 uF
COMPONENTS:
1 x IC
HA17555 or the NE555P-TI or the LM555 timer IC
Couple of x LED
5 mm LEDs (1 RED color and 1 GREEN in color)
Couple of x IC
74HCT112 Dual JK negative edge triggered Flip-Flop with
pre-set.
Resistors
¼ Watt metal film through hole resistors
2xCapacitors
One electrolytic capacitor C1=10 uF and a decoupling
ceramic capacitor C2=10 nF
Coupe of logic gates to limit the count of the counter for it to become mod 10.
1xIC
74LS47 binary-to-seven segment decoder
1xIC
Common cathode 7-segment display
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
2.6.
EQUIPMENTS: Development board
Logic Probe
Digital Multimeter
2.7.
KONOWLEDGE QUESTIONS (answer all in the report):
1. Complete the circuit diagram on the next page (555+JK’s + mod 10 limitation
circuit)
2. Determine the value of the resistors for the 555-timer circuit (R1 and R2)
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
2.8.
MARKSHEET AND GRADUATE ATTRIBUTES ASSESSMENT
Practical Experiment 2 Rubric
Subject code
DSY2602
Date
Student number
Student surname and Initials
This experiment assesses competence in terms of graduate attribute 4 (GA4) which has to do with
the ability of the student to successfully conduct an investigation, an experiment and analyse the
obtained data in form of a technical report and knowledge questions in this particular case.
N.B: Points allocated under description column are the maximum points that can be obtained.
No
1
Mark = Point x Weight
Total (%) = sum of marks
Criteria
Description
Point
The 555 timer The 555-timer circuit is not functioning at all (0 point)
circuit
Weight
5
Mark
The 555-timer circuit generates a signal at the correct
frequency but the wrong duty cycle or vice versa.
(2 point)
The 555 timer generates a signal at the correct
frequency and the correct duty cycle (4 points)
2
The counter
circuit
The counter circuit does not count at all.
point)
(0
10
The counter circuit counts properly but does not get
limited at 9 (mod 10). Instead, it carries on till 15.
(3 point)
The counter circuit counts correctly up to a value of 9
(mod 10) and then resets back to zero as expected.
(4 points)
3
Display
functioning
correctly
The display does not work at all (0 point)
10
The display works for some of the values between 0
and 9 but not for others. (1 point)
The display perfectly works for all values from 0 to 9
(mod 10).
(2 points)
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PRACTICAL TUTORIAL
4
Neatness of
the circuit
Student's circuit is untidy. Connection wires are
connected in disorder.
(0 point)
Student's circuit is moderately neat.
2
(1 points)
Student's circuit is very neat. Connection wires and
components very well placed on the board.
(5 points)
5
Technical
Report and
Knowledge
Questions
Technical report not according to the provided
template and no question out of the 9 questions
correctly answered. (0 point)
2
Correct report template used, and knowledge
questions answered. (5 points): (1 point for correct
template used and 2 points per correct answer for
questions Q1 to Q2)
Total (%)
Assessor's
Signature
29
Assessor's
surname and
initials
Student's Signature
GRADUATE ATTRIBUTES (GAs) ASSESSMENT (Decision: Met, Not met)
Score (0Decision (Met if score 3 and higher, Not met
GAs
5)
otherwise)
=Total/20
GA4
Overall Comment
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
PRACTICAL EXPERIMENT 3
DESIGN AND IMPLEMENTATION OF BASIC SHIFT REGISTER CIRCUIT WITH
LATCHED OUTPUT
Surname &
Student Number:
Initials:
3.1.
OBJECTIVE:
To build and demonstrate the operation of a 1-8 bits serial in parallel out (SIPO) shift
register circuit.
3.2.
REFERENCE:
Manufacturer’s data sheets of the 74LS164 shift register IC and the 74LS373 octal dtype flip-flop with 3-state output.
3.3.
CIRCUIT DIAGRAM:
Figure 3: Experiment 3 Circuit diagram
3.4.
DESIGN SPECIFICATIONS:
•
Input data (data In) must be provided by means of a push button switch
configured in normally HIGH normally open mode.
•
The clock signal (Clock) comes from the 555 timer circuit built in
experiment 2 (Frequency= 10 Hz, Duty Cycle=50% and C1=10 uF)
•
The Enable input comes must be provided by means of a push button
switch configured in normally LOW normally open mode.
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
•
8x 5mm LEDs are used as indicators with the a YELLOW LED for the
Least Significant Bit (LSB), a RED LED for the Most Significant Bit (MSB)
while the 6 other in between LEDs are GREEN LEDs.
3.5.
COMPONENTS:
1 x IC
74LS164 serial-in parallel out shift register
8 of x LED
5 mm LEDs (1 RED, 6 GREEN and 1 YELLOW)
1 x IC
74LS373 octal d-type flip-flop with 3-state output
Resistors
¼ Watt metal film through hole resistors
2xCapacitors
One electrolytic capacitor C1=10 uF and a decoupling
ceramic capacitor C2=10 nF
3.6.
EQUIPMENTS: Development board
Logic Probe
Digital Multimeter
3.7.
KONOWLEDGE QUESTIONS (answer all in the report):
1. MONOSTABLE CIRCUIT
1.1 Tabulate the output values for a 555-timer monostable circuit.
1.2 Draw a neat, fully labelled circuit diagram. Wire tracks must only be
horizontal or vertical and NOT cross over or under any component.
2. INPUT/OUTPUT CIRCUITS
2.1 Draw fully labelled circuit diagrams, and build the following circuits (Write
down the status/logic level of the output when the switch is pressed or
released.):
2.1.1 Normally HIGH input circuit with NO (normally open) push button switch.
2.1.2 Normally LOW input circuit with NO push button switch.
2.1.3 Normally HIGH input circuit with NC (normally closed) push button switch.
2.1.4 Normally LOW input circuit with NC push button switch.
2.2 Draw fully labeled circuit diagrams, and build the following circuits (Write
down the status/logic level of the input and mention whether the LED will glow or
not.):
2.2.1 Current Sourcing LED output circuit.
2.2.2 Current Sinking LED output circuit.
2.3 Show with the aid of circuit diagrams the difference between pull up and pull
down resistors.
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PRACTICAL TUTORIAL
3.8.
MARKSHEET AND GRADUATE ATTRIBUTES ASSESSMENT
Practical Experiment 3 Rubric
Subject code
DSY2602
Date
Student number
Student surname and Initials
This experiment assesses competence in terms of graduate attribute 4 (GA4) which has to do with
the ability of the student to successfully conduct an investigation, an experiment and analyse the
obtained data in form of a technical report and knowledge questions in this particular case.
N.B: Points allocated under description column are the maximum points that can be obtained.
No
1
Mark = Point x Weight
Total (%) = sum of marks
Criteria
Description
Point
The 555-timer The 555-timer circuit is not functioning at all (0 point)
circuit
Weight
5
Mark
The 555-timer circuit generates a signal at the correct
frequency but the wrong duty cycle or vice versa.
(1 point)
The 555 timer generates a signal at the correct
frequency and the correct duty cycle (2 points)
2
The shift
register circuit
No data is being shifted on the output of the shift
register (0 point)
20
The data are being shifted to the output of the shift
register but not in synchronization with the clock or
at a wrong speed.
(1 point)
The data are being shifted to the output of the shift
register in synchronization with the clock at the
correct.
(2 points)
3
The latch
circuit
No data is being latched to the output of the latch
circuit (0 point)
10
The 8 bits of data are being latched to the output but
with a delay. (1 point)
The 8 bits of data are being latched to the output in
real-time. (2 point)
4
Neatness of
the circuit
Student's circuit is untidy. Connection wires are
connected in disorder.
(0 point)
DIGITAL SYSTEMS II
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5
PRACTICAL TUTORIAL
Student's circuit is moderately neat.
(1 points)
Student's circuit is very neat. Connection wires and
components very well placed on the board.
(2 points)
5
Technical
Report and
Knowledge
Questions
Technical report not according to the provided
template and no question out of the 9 questions
correctly answered. (0 point)
2
Correct report template used, and knowledge
questions answered. (10 points): (1 point for correct
template used and 4 points for correct knowledge
answers to questions Q1 and 5 marks for correct
knowledge answers on question 2).
Total (%)
42
Assessor's
surname and
initials
Assessor's
Signature
Student's Signature
GRADUATE ATTRIBUTES (GAs) ASSESSMENT (Decision: Met, Not met)
GAs
Score (0-5)
=Total/20
Decision (Met if score 3 and higher, Not
met otherwise)
GA4
Overall Comment
N.B:
DIGITAL SYSTEMS II
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PRACTICAL TUTORIAL
Overall, you are given up to three opportunities (one per experiment) to
achieve the graduate attribute (GA4). You will need to meet its
requirements in at least two experiments out of three to have it ticked as
achieved.
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