COMPSCI110: pass the exams, not just read the notes
Your complete guide to University of Auckland's introduction to computer systems course. See where the marks are, work real practice questions, and study with an AI tutor that knows COMPSCI110.
Sia generates COMPSCI110 practice questions, walks through introduction to computer systems and binary arithmetic step by step, and quizzes you on the material the exam weights most heavily.
Worked example
An 8-bit register holds the two's complement value 1101 0110. What is this value in decimal, and what happens if you add 0011 1010 to it in the same 8-bit register?
Read the sign bit first. The leading bit is 1, so in two's complement this is a negative number. Do not read it as unsigned 214.
Now add without thinking about sign: 1101 0110 + 0011 1010. Working right to left with carries gives 1 0001 0000, and the ninth bit falls out of the 8-bit register, leaving 0001 0000 = +16.
Check overflow properly. Overflow in two's complement is signalled when the two operands share a sign and the result has the opposite sign, not by a carry out. Here the operands have different signs (-42 and +58), so overflow is impossible. The carry out is discarded and the answer -42 + 58 = +16 is correct.
The trap: Treating the carry out of the most significant bit as an overflow. In unsigned arithmetic a carry out does mean overflow, but in two's complement it does not. Overflow only occurs when two operands of the same sign produce a result of the opposite sign. Option B fails on exactly this point, and option C fails by reading a signed register as unsigned. classic slip!
One exam decides 50% of your grade. Controlled assessment (Lane 1): AI tools are prohibited. This whole page is built around that.
Overview
What COMPSCI110 is, and where it sits
COMPSCI 110 is the University of Auckland's guided tour of the whole computer, from a single bit up to the web. the prescription describes it as an introduction to the layers that make up a modern computer system: encoding of data and instructions, hardware, low-level programming, operating systems, applications and communications. It is compulsory for the Computer Science major and cannot be taken with or after COMPSCI 210.
The course is unusual in how wide it ranges. In one semester you move through binary and floating-point representation, Boolean logic and circuits, von Neumann architecture, assembly language, algorithms and pseudocode, computer networks, compilation, operating systems, encryption and finally the theory of computation and neural networks. Each module is shallow enough to be learned in a week and deep enough that the exam can ask you to do the work by hand.
What decides your grade is the split between theory and practice. Seventy percent of the marks sit in the mid-semester test and the final exam, both run as controlled assessments where AI tools are prohibited. The remaining thirty percent comes from assignments, essays and tutorials, where AI use is permitted. You must separately pass both halves, which is the single rule that catches most students who get into trouble.
Always treat your own course outline and the exam timetable as authoritative.
Difficulty & time commitment
Is COMPSCI110 hard, and how much time does it take?
COMPSCI110 is manageable if you keep a weekly rhythm and treat the back half as the main event. The pattern is consistent: it starts gently and steepens, and the heaviest assessment is the part that separates grades.
The difficulty curve and the assessment weighting point the same way: the back half is harder and worth more. Front-loading effort there is the highest-return decision in the course.
Is this course for you
Who tends to do well, and who tends to struggle
You will likely do well if
- You can do base conversion, two's complement arithmetic and floating-point encoding accurately and quickly by hand, without a calculator and without hesitating over the method.
- You keep the two lanes separate in your head: you practise the controlled skills unaided, and you use the permitted tools only where the course allows them.
- You treat each module as a self-contained unit with its own vocabulary, and you build a one-page summary per module as you go rather than at the end.
- You are comfortable moving between very different levels of abstraction in the same week, from a logic gate to a network protocol.
You may struggle if
- You let the coursework carry you and assume the overall mark is what counts. The dual-pass rule means a failed theory component ends the course regardless of your assignment marks.
- You rely on AI assistance for the assignment work and never build the manual fluency the test and exam demand.
- You leave the breadth to the end. Ten modules cannot be compressed into a revision week, and the exam samples all of them.
- You read the material rather than working it. Tracing an assembly program or filling a truth table is a skill that only comes from doing it repeatedly.
- Build a module-by-module skills card: for each module write the one mechanical procedure the exam will ask you to perform, then rehearse it until it is automatic.
- Practise the conversions under time pressure. Marks in the early modules are lost to arithmetic slips, not to misunderstanding.
- For the networks module, learn the four delay components and be able to compute an end-to-end delay, since networks carries the largest published question count in the exam breakdown.
- Do not neglect the discussion modules. Ethics, security and theory of computation questions are answerable in full if you have the vocabulary, and they are the cheapest marks in the paper for a well-prepared student.
Syllabus
The 12 topics, module by module
The exam-weight marker on each topic shows where the marks concentrate. The amber topics carry the highest exam weight.
T1 · Introduction to computer systems and binary numbers
Schneider and Gerstang Ch 1 to 2The layered model of a computer system, and unsigned binary representation: converting between decimal, binary, octal and hexadecimal.
T2 · Binary arithmetic and signed values
Schneider and Gerstang Ch 4Addition and subtraction in binary, sign-magnitude, one's complement and two's complement, and overflow detection.
T3 · Binary fractions and floating point
Schneider and Gerstang Ch 4Fixed-point fractions, normalised floating-point form, mantissa and exponent fields, and rounding error.
T4 · Encoding text and other data
Schneider and Gerstang Ch 4ASCII and Unicode, run-length encoding and Huffman coding, and why compression is a trade against decode cost.
T5 · Boolean logic and gates
Schneider and Gerstang Ch 4Truth tables, AND, OR, NOT, NAND, NOR and XOR, and reading a gate diagram back into a Boolean expression.
T6 · Building functions from gates
Schneider and Gerstang Ch 4Going from a truth table to a sum-of-products circuit, and simplifying before you build.
T7 · Multiplexors, decoders and sequential circuits
Schneider and Gerstang Ch 4Selecting and decoding circuits, latches and flip-flops, and the idea of state held over time.
T8 · Von Neumann architecture and computer organisation
Schneider and Gerstang Ch 5The ALU, control unit, registers and status flags, the fetch-decode-execute cycle, and the memory and input-output subsystems.
T9 · Assembly language and machine code
Schneider and Gerstang Ch 6The textbook instruction set, desk-checking an assembly program by hand, and disassembling machine code back to instructions.
T10 · Algorithms and pseudocode
Schneider and Gerstang Ch 2 to 3Expressing a solution as unambiguous pseudocode, and tracing it to confirm it does what the specification asks.
T11 · Computer networks and the internet
Schneider and Gerstang Ch 7Packet versus circuit switching, the ISP hierarchy, protocol layering, and the four sources of delay in a network path.
T12 · Compilation, operating systems, security and theory of computation
Schneider and Gerstang Ch 6, 8 and 11 to 13Lexical analysis, parsing and code generation; process scheduling, deadlock, memory management and file systems; symmetric and asymmetric encryption and digital certificates; Turing machines, the Church-Turing thesis and neural networks.
How it's assessed
Assessment structure
| Component | Weight | Format & timing |
|---|---|---|
| Final exam | 50% | Invigilated final examination organised by module, with multiple choice, text and numeric entry, matching, inline choice and composite questions. University of Auckland Semester 1 examination period. Controlled assessment (Lane 1): AI tools are prohibited. |
| Mid-semester test | 20% | Invigilated test of about 20 questions spanning binary numbers and arithmetic, floating point, encoding, Boolean logic and gates, multiplexors and sequential circuits, von Neumann architecture, assembly and pseudocode. Mid-semester. Controlled assessment (Lane 1): AI tools are prohibited. |
| Assignments | 20% | Practical assignments applying the module content. Across the semester. Uncontrolled assessment (Lane 2): AI tools are permitted. |
| Essays | 8% | Short written pieces, including the ethics and societal-impact strand of the course. Across the semester. Uncontrolled assessment (Lane 2): AI tools are permitted. |
| Tutorials | 2% | Tutorial participation and exercises. Weekly. Uncontrolled assessment (Lane 2): AI tools are permitted. |
- You must separately pass both the theory component (mid-semester test and final exam) and the practical component (assignments, essays and tutorials). Passing on the combined total alone is not sufficient.
- The final exam is organised by module rather than by question type, so revision maps cleanly onto the module list. Published breakdowns for Semester 1, 2026 show roughly four questions on binary and base conversion, three on logic and circuits, two on computer organisation, two on assembly and five on computer networks, with the remaining modules (operating systems, security, theory) making up the balance.
This is an exam-cram course. With the exams at 50% of the grade and the final exam alone at 50%, your result is overwhelmingly decided by how well you perform under time pressure. Controlled assessment (Lane 1): AI tools are prohibited.
Final exam timing: During the University of Auckland Semester 1 examination period. Confirm the exact date and venue on your exam timetable.
How to actually pass it
A weekly rhythm, two checklists, and the traps to avoid
The course rewards consistency over cramming, and practice over re-reading. Here is the loop that works, then what to have nailed before each exam.
The weekly loop
Before the mid-semester checklist
- Convert fluently between decimal, binary, octal and hexadecimal in both directions.
- Add and subtract in two's complement, and correctly identify when overflow has occurred as opposed to a discarded carry.
- Normalise a binary fraction into floating-point form and read one back to decimal.
- Build a truth table from a gate diagram and a sum-of-products circuit from a truth table, and trace a short assembly program by desk check.
Before the final heaviest topics
- Cover every module, since the exam is organised by module and samples across all of them.
- Rehearse the mechanical procedures from Modules 1 to 4 until they are automatic, because these carry the highest question counts.
- Learn the networks module properly: packet versus circuit switching, the ISP hierarchy, layering and the four sources of delay.
- Prepare the discussion modules with vocabulary you can deploy: compilation phases, process scheduling and deadlock, memory management, symmetric versus asymmetric encryption, the Turing machine model and the Church-Turing thesis.
The mistakes that cost marks
Reading a signed register as unsigned. When the leading bit is 1 the value is negative in two's complement. Students routinely convert 1101 0110 to 214 instead of -42. Always check the sign bit before converting.
Confusing carry out with overflow. A carry out of the most significant bit is normal and is discarded. Overflow is only signalled when two operands of the same sign produce a result of the opposite sign. These are different conditions and the exam tests the difference.
Ignoring the practical component. Assignments, essays and tutorials are only 30% of the grade but they form a separately assessed component. Skipping them fails the course even with a strong exam mark.
Treating the theory modules as unexaminable. Operating systems, security and theory of computation appear in the exam alongside the mechanical modules. They are often the best-value marks because they reward preparation rather than speed.
Teaching team
Who teaches COMPSCI110
The bios below are factual. We do not rate lecturers; any star ratings are submitted by students who have taken COMPSCI110.
Asma Shakil
Coordinates COMPSCI 110 and teaches across the course modules in the School of Computer Science.
Aniket Mahanti
Teaches on COMPSCI 110 in the School of Computer Science, with research interests in computer networks and systems.
Paul Denny
Appears on the COMPSCI 110 teaching team in the School of Computer Science. Widely published in computing education research.
Teaching team as listed in public course information. AskSia does not rate lecturers; star ratings are submitted by students who have taken COMPSCI110.
Formula & concept sheet
The vocabulary and formulas you must own
- Two's complement
- The standard signed binary representation. To negate a value, invert every bit and add one. The leading bit acts as a sign indicator: 0 for non-negative, 1 for negative.
- Overflow condition
- In two's complement, overflow occurs only when both operands share a sign and the result carries the opposite sign. A carry out of the most significant bit is not itself overflow.
- Normalised floating point
- A value expressed as a signed mantissa multiplied by the base raised to an exponent, with the mantissa constrained to a fixed range so the representation is unique.
- Run-length encoding
- A lossless compression scheme that stores a repeated symbol once alongside its repeat count. Effective on data with long runs, counterproductive on data without them.
- Huffman coding
- A lossless compression scheme that assigns shorter bit codes to more frequent symbols, building the code from a frequency-ordered binary tree.
- Sum of products
- A Boolean expression built by writing one AND term for each row of the truth table that outputs 1, then combining those terms with OR.
- Multiplexor
- A circuit that selects one of several data inputs and routes it to a single output, controlled by a set of select lines.
- Von Neumann architecture
- The design in which instructions and data share one memory, executed by a control unit and arithmetic logic unit through the fetch-decode-execute cycle.
- Fetch-decode-execute cycle
- The repeating three-phase operation of a processor: retrieve the next instruction from memory, interpret it, then carry it out and update the status registers.
- Packet switching
- A network method that splits a message into packets routed independently and reassembled at the destination, sharing link capacity rather than reserving it.
- Protocol layering
- The organisation of network functions into stacked layers, each providing a service to the layer above and relying on the layer below.
- Church-Turing thesis
- The proposition that any function that can be effectively computed by any means can be computed by a Turing machine, which fixes the boundary of what is computable.
Common acronyms: ALU · ASCII · CPU · DNS · ISP · LAN · MUX · OS · RAM · TCP.
Set texts
The prescribed reading
The syllabus references map straight onto these.
Invitation to Computer Science, 8th edition
Schneider and Gerstang.
Where it fits
Prerequisites, related courses & why it matters
No formal prerequisite. COMPSCI 110 is compulsory for the Computer Science major and cannot be taken with or after COMPSCI 210. It pairs naturally with COMPSCI 101 in a first-year computer science programme.
Your COMPSCI110 study toolkit
Study the course with Sia, not just read about it
Each tool already knows COMPSCI110: your syllabus, your texts, and where the marks are. Grouped by how you study, from first contact to exam week.
FAQ
Frequently asked questions
Is COMPSCI 110 hard?
It sits at moderately hard. No single module is conceptually brutal, but the course covers ten distinct areas in one semester and the 50% final exam can reach into any of them. Students who treat it as ten small subjects rather than one large one tend to do well.
What is the dual-pass requirement and why does it matter?
You must separately pass the theory component (mid-semester test and final exam) and the practical component (assignments, essays and tutorials). This means a student who coasts on assignments but fails the exam does not pass, and neither does a strong exam candidate who skipped the coursework. It is the most common way to fail this course despite an adequate overall mark.
Can I use AI tools in COMPSCI 110?
It depends on the assessment. The course runs a two-lane policy. The mid-semester test and final exam are Lane 1, controlled, where AI tools are prohibited. Assignments, essays and tutorials are Lane 2, uncontrolled, where AI use is permitted. Because 70% of the grade sits in Lane 1, the skills you actually need are the ones you can perform unaided.
Do I need to be good at maths?
You need to be comfortable and accurate with arithmetic in different bases, two's complement, floating-point normalisation and Boolean algebra. None of it requires calculus, but all of it is mechanical work that must be done exactly. Speed and accuracy matter more than mathematical sophistication.
What textbook does COMPSCI 110 use?
The required text is Invitation to Computer Science, 8th edition, by Schneider and Gerstang, published by Cengage (ISBN 9781337561914). The course specifies the textbook or ebook version rather than the online learning platform version.
How should I revise for the final exam?
Revise by module, because the exam is built that way. Work through the published module structure and make sure you can perform each mechanical skill by hand: base conversion, two's complement arithmetic, floating-point encoding, truth tables to circuits, a fetch-decode-execute trace, an assembly desk check and a network delay calculation. Then read for the discussion-style modules on operating systems, security and theory of computation.
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