ELEC1601 Introduction to Computer Systems
The Complete Exam Bible · S2 2026ELEC1601 Overview
- The University of Sydney
- Semester 2, 2026
- an undergraduate unit of study
- 6 credit points
ELEC1601 Introduction to Computer Systems develops a bottom-up account of digital representation, computer architecture and AVR assembly alongside top-down Arduino laboratories and a team project. It is taught within University of Sydney School of Electrical and Computer Engineering. It is an undergraduate unit of study.
- ELEC1601 grading Fundamentals Quizzes 20% · Extension Quizzes 10% · Essential Lab Completion 15% · 5 more published item(s)
- ELEC1601 task mode Plan around this operating format: The 35% final is a two-hour written examination in the formal exam period.
- ELEC1601 pressure point The main transfer challenge is this: Maintaining one coherent model across binary representation, registers, memory addresses, stack state and control flow.
- ELEC1601 pass rule Before relying on the total mark, apply this control: The official outline marks the written exam, fundamentals quizzes, essential lab completion, laboratory attendance and essential project as hurdle tasks. All essential assessments must be passed, and participation in the lab is compulsory, to pass the unit.
How ELEC1601 is assessed
| Component | Weight | Format |
|---|---|---|
| Fundamentals Quizzes · hurdle | 20% | Four in-person essential quizzes; hurdle task |
| Extension Quizzes | 10% | Three in-person quizzes testing extension knowledge |
| Essential Lab Completion · hurdle | 15% | Group laboratory work with individual explanation; hurdle task |
| Laboratory Attendance · hurdle | 0% | Participation and group sign-up; hurdle task |
| Essential Project · hurdle | 10% | Group project assessed through demonstration and Q&A; hurdle task |
| Extension Project | 5% | Extension-level project criteria |
| Advanced Project | 5% | Advanced-level project criteria |
| Final exam · hurdle | 35% | Two-hour mandatory written exam; AI prohibited; hurdle task |
The 2026 official outline publishes eight weighted rows totalling 100%. The final exam is 35% and mandatory. Fundamentals quizzes, essential lab completion, laboratory attendance, essential project and the written exam are hurdle tasks; all essential assessments must be passed.
What ELEC1601 covers
The learning path moves from Computer-Systems Competence, Hurdles and State Tracing, through the problems opened by Memory, Addresses and Addressing Modes, to the synthesis required in Arduino Project, Oral Defence and Final Exam.
Computer-Systems Competence, Hurdles and State Tracing
essential-extension-advanced levels · five hurdle controls · state-trace method · build an assessment ledger and use one trace format across quizzes, labs, project and examDefine essential-extension-advanced levels
Computer-Systems Competence, Hurdles and State Tracing turns essential-extension-advanced levels, five hurdle controls and state-trace method into executable reasoning.
- essential-extension-advanced levels
- five hurdle controls
- state-trace method
- Applying essential-extension-advanced levels
- Limits of five hurdle controls and state-trace method
Programming, Loops, Polling and Interrupts
program state · polling loop · interrupt-driven response · trace when a microcontroller reads an input and changes an output under polling and interrupt designsDefine program state
Programming, Loops, Polling and Interrupts turns program state, polling loop and interrupt-driven response into executable reasoning.
- program state
- polling loop
- interrupt-driven response
- Applying program state
- Limits of polling loop and interrupt-driven response
Binary, Hexadecimal and Signed Integers
positional binary · hexadecimal notation · two's-complement integers · convert representations and detect the signed range and overflow of a fixed-width operationDefine positional binary
Binary, Hexadecimal and Signed Integers turns positional binary, hexadecimal notation and two's-complement integers into executable reasoning.
- positional binary
- hexadecimal notation
- two's-complement integers
- Applying positional binary
- Limits of hexadecimal notation and two's-complement integers
Fixed-Point, Floating-Point and Encoding
fixed-point scale · floating-point fields · precision and range · encode a value and explain the rounding, overflow and comparison consequences of the chosen representationDefine fixed-point scale
Fixed-Point, Floating-Point and Encoding turns fixed-point scale, floating-point fields and precision and range into executable reasoning.
- fixed-point scale
- floating-point fields
- precision and range
- Applying fixed-point scale
- Limits of floating-point fields and precision and range
AVR Assembly Language and the Instruction Set
instruction mnemonic · register operands · status flags · translate a small operation into AVR instructions and trace each register and flag changeDefine instruction mnemonic
AVR Assembly Language and the Instruction Set turns instruction mnemonic, register operands and status flags into executable reasoning.
- instruction mnemonic
- register operands
- status flags
- Applying instruction mnemonic
- Limits of register operands and status flags
Computer Architecture: CPU, Registers and Memory
CPU datapath · register file · program and data memory · connect an instruction's encoding to fetch, decode, execute and visible machine stateDefine CPU datapath
Computer Architecture: CPU, Registers and Memory turns CPU datapath, register file and program and data memory into executable reasoning.
- CPU datapath
- register file
- program and data memory
- Applying CPU datapath
- Limits of register file and program and data memory
Memory, Addresses and Addressing Modes
byte address · pointer register · direct and indirect addressing · calculate the accessed location and show how pointer updates change later reads or writesDefine byte address
Memory, Addresses and Addressing Modes turns byte address, pointer register and direct and indirect addressing into executable reasoning.
- byte address
- pointer register
- direct and indirect addressing
- Applying byte address
- Limits of pointer register and direct and indirect addressing
The Runtime Stack and Stack Pointer
stack pointer · push and pop · activation record · trace the stack across nested calls and recover the caller's state and return addressDefine stack pointer
The Runtime Stack and Stack Pointer turns stack pointer, push and pop and activation record into executable reasoning.
- stack pointer
- push and pop
- activation record
- Applying stack pointer
- Limits of push and pop and activation record
Subroutines and Calling Conventions
call and return · parameter passing · caller- and callee-saved state · design a subroutine interface and prove that registers, arguments and results survive the call correctlyDefine call and return
Subroutines and Calling Conventions turns call and return, parameter passing and caller- and callee-saved state into executable reasoning.
- call and return
- parameter passing
- caller- and callee-saved state
- Applying call and return
- Limits of parameter passing and caller- and callee-saved state
Control Flow, Branches and AVR Loops
condition flags · branch instruction · loop invariant · compile a structured loop into branches and demonstrate termination and boundary behaviourDefine condition flags
Control Flow, Branches and AVR Loops turns condition flags, branch instruction and loop invariant into executable reasoning.
- condition flags
- branch instruction
- loop invariant
- Applying condition flags
- Limits of branch instruction and loop invariant
Compilers and High-Level Programming Constructs
source-level construct · assembly translation · optimisation and equivalence · relate a C-level expression, branch or function to its AVR assembly and explain an optimisation safelyDefine source-level construct
Compilers and High-Level Programming Constructs turns source-level construct, assembly translation and optimisation and equivalence into executable reasoning.
- source-level construct
- assembly translation
- optimisation and equivalence
- Applying source-level construct
- Limits of assembly translation and optimisation and equivalence
Arduino Project, Oral Defence and Final Exam
sensor-actuator loop · team implementation · explainable evidence · scope, build and test the artefact, then defend the bit-level and instruction-level logic without AI assistanceDefine sensor-actuator loop
Arduino Project, Oral Defence and Final Exam turns sensor-actuator loop, team implementation and explainable evidence into executable reasoning.
- sensor-actuator loop
- team implementation
- explainable evidence
- Applying sensor-actuator loop
- Limits of team implementation and explainable evidence
It carries 6 credit points. It is positioned as a core introductory computer-systems unit in relevant engineering programs.
The lecture sequence follows information from bits and encodings into instructions, memory, stacks, subroutines and compiler translation.
Laboratories approach the same machine from sensors, actuators and programmed behaviour, so strong answers connect the representation in memory with the observable action of the physical or simulated system.
Assessment in ELEC1601 is distributed as follows: 35% written final exam, 20% fundamentals quizzes, 10% extension quizzes, 15% essential lab completion, 0% laboratory attendance, and three project levels worth 10%, 5% and 5%
The operational assessment conditions matter here.
The 35% final is a two-hour written examination in the formal exam period. Attendance is mandatory; the mandatory section uses multiple-choice questions based on in-semester tests, while the advanced section carries a threshold for extra marks.
AI is prohibited.
What makes ELEC1601 demanding is concrete: Maintaining one coherent model across binary representation, registers, memory addresses, stack state and control flow.
Code can appear to work while the student cannot explain which bits represent the value, which instruction changed the state or why a call and return preserve the required registers.
The official outline marks the written exam, fundamentals quizzes, essential lab completion, laboratory attendance and essential project as hurdle tasks.
All essential assessments must be passed, and participation in the lab is compulsory, to pass the unit.
For enrolment planning, The 2026 unit page lists no prerequisite or corequisite and assumes HSC Mathematics Extension 1 or 2.
The learning path moves from Computer-Systems Competence, Hurdles and State Tracing, through the problems opened by Memory, Addresses and Addressing Modes, to the synthesis required in Arduino Project, Oral Defence and Final Exam.
Coverage note: older Canvas pages contain a superseded optional 30% exam; all assessment claims here use the 2026 official outline instead.
Worked example · free
Trace one signed byte from representation to machine meaning
- 1Write +18 as the 8-bit pattern 00010010.
- 1Invert the bits and add one to obtain the negative representation.
- 1Group the result into nibbles and convert it to hexadecimal.
- 1State how signedness changes interpretation without changing the bits.
Key terms
- AVR assembly language
- A symbolic low-level language whose mnemonics encode operations executed by an AVR microcontroller instruction set.
- Binary number system
- A positional numeral system using base two, with each digit representing a power of two.
- Two's complement
- A fixed-width signed-integer representation in which negation is formed by inverting bits and adding one.
- Fixed-point representation
- A numeric encoding that assigns an agreed fixed position to the binary radix point.
- Floating-point representation
- A numeric encoding using sign, significand and exponent fields to represent values across a wide range.
- Computer architecture
- The programmer-visible organisation of a computer, including its instruction set, registers, memory model and data paths.
- Stack pointer
- A register holding the address that identifies the current top boundary of the runtime stack.
- Subroutine
- A reusable instruction sequence entered by a call and completed by returning control to its caller.
- Polling
- A control technique in which software repeatedly checks a device or condition to determine whether an event requires service.
ELEC1601 FAQ
Does ELEC1601 have a hurdle or component-level pass rule?
The official outline marks the written exam, fundamentals quizzes, essential lab completion, laboratory attendance and essential project as hurdle tasks. All essential assessments must be passed, and participation in the lab is compulsory, to pass the unit.
How is ELEC1601 assessed?
35% written final exam, 20% fundamentals quizzes, 10% extension quizzes, 15% essential lab completion, 0% laboratory attendance, and three project levels worth 10%, 5% and 5%
What is the ELEC1601 exam or final-task format?
The 35% final is a two-hour written examination in the formal exam period. Attendance is mandatory; the mandatory section uses multiple-choice questions based on in-semester tests, while the advanced section carries a threshold for extra marks. AI is prohibited.
Where do students usually lose marks in ELEC1601?
Maintaining one coherent model across binary representation, registers, memory addresses, stack state and control flow. Code can appear to work while the student cannot explain which bits represent the value, which instruction changed the state or why a call and return preserve the required registers.
Which offering does this ELEC1601 guide cover?
It is aligned to Semester 2, 2026; confirm your enrolled class and timetable in the current institutional system.
What prerequisites or restrictions apply to ELEC1601?
The 2026 unit page lists no prerequisite or corequisite and assumes HSC Mathematics Extension 1 or 2.
Is this ELEC1601 resource an official university guide?
No. It is an independent ELEC1601 study resource; current institutional instructions remain authoritative for assessment operation.
Questions students ask in each ELEC1601 chapter
- What is the main task in Computer-Systems Competence, Hurdles and State Tracing?
- Build an assessment ledger and use one trace format across quizzes, labs, project and exam. Chapter 01 · Computer-Systems Competence, Hurdles and State Tracing
- What is the main task in Programming, Loops, Polling and Interrupts?
- Trace when a microcontroller reads an input and changes an output under polling and interrupt designs. Chapter 02 · Programming, Loops, Polling and Interrupts
- What is the main task in Binary, Hexadecimal and Signed Integers?
- Convert representations and detect the signed range and overflow of a fixed-width operation. Chapter 03 · Binary, Hexadecimal and Signed Integers
- What is the main task in Fixed-Point, Floating-Point and Encoding?
- Encode a value and explain the rounding, overflow and comparison consequences of the chosen representation. Chapter 04 · Fixed-Point, Floating-Point and Encoding
- What is the main task in AVR Assembly Language and the Instruction Set?
- Translate a small operation into avr instructions and trace each register and flag change. Chapter 05 · AVR Assembly Language and the Instruction Set
- What is the main task in Computer Architecture: CPU, Registers and Memory?
- Connect an instruction's encoding to fetch, decode, execute and visible machine state. Chapter 06 · Computer Architecture: CPU, Registers and Memory
- What is the main task in Memory, Addresses and Addressing Modes?
- Calculate the accessed location and show how pointer updates change later reads or writes. Chapter 07 · Memory, Addresses and Addressing Modes
- What is the main task in The Runtime Stack and Stack Pointer?
- Trace the stack across nested calls and recover the caller's state and return address. Chapter 08 · The Runtime Stack and Stack Pointer
- What is the main task in Subroutines and Calling Conventions?
- Design a subroutine interface and prove that registers, arguments and results survive the call correctly. Chapter 09 · Subroutines and Calling Conventions
- What is the main task in Control Flow, Branches and AVR Loops?
- Compile a structured loop into branches and demonstrate termination and boundary behaviour. Chapter 10 · Control Flow, Branches and AVR Loops
- What is the main task in Compilers and High-Level Programming Constructs?
- Relate a c-level expression, branch or function to its avr assembly and explain an optimisation safely. Chapter 11 · Compilers and High-Level Programming Constructs
- What is the main task in Arduino Project, Oral Defence and Final Exam?
- Scope, build and test the artefact, then defend the bit-level and instruction-level logic without ai assistance. Chapter 12 · Arduino Project, Oral Defence and Final Exam
How to study for the exam
Retrieve the course map, practise the recurring method—represent the data at bit level, trace the instructions and machine state, connect the trace to hardware behaviour and test the result on normal, boundary and failure cases—on changed scenarios, and verify every operational assessment detail in the live institutional system.
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