CS255 Syllabus & Progress

Material covered are displayed in blue.

Intro to CS255: click here

Search the lecture notes:

Review of Computer Architecture and Intro to Program Organization

Logical View of a Computer System: click here
Structure of computer main memory: click here
Accessing the computer memory: click here
Program organization (where different parts of the program is put in memory): click here -- will be explained in Section 4 in detail
The program translation process: click here -- will be explained in Section 5 in detail

Before we can explain how the computer works - i.e., how it manipulates data, we must understand how information are stored inside the computer...

How information are stored in the computer

Fundamental data used in the computer (these values need to be stored)
- Numbers (int, float, double)
- Text (char)
- Computer instructions
- (Boolean values "true" is represented as the number 1 and "false" as number 0)
Storing numeric values inside the computer:
- Numeric values: click here
- Positional value representation: click here
- Representing unsigned integers: click here
- Arithmetic with binary numbers: click here
Other number systems:
- Base-5 numbers: click here
- Octal numbers: click here
- Hexadecimal numbers: click here
Representing Signed integers: click here
- 10's complement number encoding: click here
- 2's complement number encoding: click here
- "Excess-n": an alternate binary encoding for signed values: click here
Fixed point numbers: click here
Floating point numbers
- Floating point representation: click here
- Floating point round off error: Float.java
Homework 1 re-enforces number system concepts: click here
A binary number information sheet: click here

Representing alphanumerical (textual) data inside the computer:

ASCII code: click here
Unicode: click here
What's that in the memory ? click here

Making communication possible between humans and computers:

Introduction: click here
Communicating non-textual information to a computer:
- Communicating Boolean values between humans and computers: click here
- Communicating numerical values between humans and computers:
  - A trivial solution: click here
  - Working with ASCII codes: click here
  - Some Java facts: click here
  - Communicating numerical values between humans and computers: click here
  Homework 2 re-enforces string <-> binary conversion: click here

Storing computer instructions inside the computer:

Instruction categories:
- 0 operand
- 1 operand (unary operation, e.g., negate)
- 2 operands (binary operation, e.g., add)
Instruction formats:
- Variable length (Intel, Motorola M68000)
- Fixed length (SPARC, MIPS)
M68000 Instruction encoding: click here
SPARC Instruction encoding: click here

Intro to computer programming: anatomy of computer programs and how to make a computer program

What's in a computer program (instructions + variables in memory cells): click here
The general CPU architecture (= machinery to execute computer instructions): click here
The instruction execution cycle (how the CPU works): click here
Evolution of the art of "programming a computer": click here
Example of translating high level language program: click here

Intro to M68000 assembler programming

Why assembler programming ? click here
M68000 CPU architecture: click here
Structure of an (M68000) assembler program (assembler directives and assembler instructions): click here

Assembler directives: defining constants and variables in a program

Defining (symbolic) constants in a computer program: click here
Defining variables in a computer program:
- Review: kinds of variables in Java: click here
- Intro to memory organization: click here
- How the different kinds of variables are stored in memory: click here
- Defining (uninitialized) class variables of Java in assembler programming: click here
- Defining initialized class variables of Java in assembler programming: click here
- Memory alignment requirement for variables: click here
Ending an M68000 assembler program: click here

Operands used in assembler instructions

M68000 Assembler Instruction: click here
Operands in M68000 assembler programming:
- The move instruction (used to illustrate how to access operands): click here
- Operands:
  - Intro to operands (of assembler instructions): click here
  - Data Register operands: click here
  - Address Register operands: click here
  - Memory operands:
    - Storing data in memory click here
    - Accessing data stored in memory: click here
Big and little endian storage format: click here

The Assignment Statement:

A simple example: C = A + B click here
Accessing variables: M68000 addressing modes (tough topic...)
- Immediate: click here
- Absolute or Direct: click here
  Homework 3 introduces the Egtapi programming environment, and re-enforces defining and using simple variables with Assembler Directives and the Immediate & Direct Modes: click here
  This project is very easy to do, but make sure you assemble and run the program to get familiar with Egtapi, or else, you will have major headaches with later projects
- Address register indirect (with displacement): click here
- Accessing data structures using the indirect modes:
  - Accessing arrays: click here
  - How is a linked list stored in memory: click here
  - Accesing data in linked list: click here
- Address register indirect with index and displacement: click here
M68000 instruction nmenomic codes and the allowed addressing modes: click here
M68000 instruction nmenomic codes and their meaning: click here
All M68000 instructions discussed in CS255 (work in progress): click here

Arithmetic operations (+, -, * and /):

The data type in an operation: click here
Important property of computer (= machine) instructions: click here
Arithmetic operations on the operands of the same data type:
- The add (and adda) instruction: click here
- The default type of a M68000 instruction and case sensitivity: click here
- Note on how "a + b" is translated into assembler code: click here
- The subtract (sub) instruction: click here
- The negate (neg) instruction: click here
- The muls and divs instructions (integer multiply and divide): click here
Operations on array variables of various data types: click here

Computations using different types of variables:

Mixing int, short, byte operands:
- Assembler instructions to convert between different data types : click here
- Assignment statement using different sizes: click here
- Arithmetic expression using different sizes: click here
- Mixed type operations with array variables: click here
- Using the ext instruction on the results of the muls and divs instructions:
  - Multiply: click here
  - Divide: click here
- A large example accessing data structures (includes linked list): click here

"Complicated" functions - like sin(x): click here

Homework 4 re-enforces using array variables and size conversion with M68000 assembler instructions: click here

Now you know what the computer actually does when it executes an assignment statement: how it evaluates an expression and assigns the result to a variable in a high level programming language

The Selection (if, if-else) Statements:

The Compare (cmp) and Branch instructions of M68000: click here
Selection statements in assembler:
- Simple if: click here
- Simple if-else: click here
- Compound condition using and: click here
- Compound condition using or: click here
- Nested If-statements: click here

Repetition statements in assembler:

While-statment: click here
For-statment: click here
Do-statment: do.s.
Traversing linked lists: click here

Homework 5 re-enforces the use of compare and branching in writing your first assembler program containing a while loop and an if-statements: click here

The midterm test will cover the material upto this point

Now you know what the computer actually does when it runs a program. The only thing that you still do not know is what happens in a function call (there is still a lot to learn...).

Programming project hw6 re-enforces loop and if-statements further with a sorting algorithm... click here

Subroutines (a.k.a. methods, procedures, functions):

Prelude to subroutines: try to use BRA to implement subroutines: click here
Prelude to subroutines: implementing a stack click here
M68000 instructions for subroutine invocation and return click here
Passing parameters and return values: click here
Different ways to pass parameters to a function/subroutine:
- Pass-by-value (a.k.a. Call-by-value): click here
- Pass-by-reference (a.k.a. Call-by-reference): click here
- Important note: click here
Local variables (and parameter variables):
- Intro to Subroutine with local variables: click here
- Review: Lifetime of parameter variables and local variables: click here
- How modern programming languages store parameter and local variables:
  - Modern languages: click here
  - using the stack to pass parameters and store local variables: click here
  - using a frame pointer to access parameters and local variables: click here
Recursion:
- Reminder on parameter variables and local variable:
  - parameter variables and local variables are created when a function is invoked
  - parameter variables and local variables are destroyed when a function returns
  - We have learned how to implement this behavior using the system stack
- Writing recursive functions in assembler code:
  1. always pass parameters on the stack
  2. always use the stack to store local variables
- First recursion in assembler, the classical factorial: click here
- Another classic recursive problem -- Fibonacci numbers: click here
  
  I have some material here to help you understand how to write a recursive method --- these material are not part of CS255 curriculum:
  - Review CS170: recursion is a divide and conquer technique to solve problems: click here
  - Review CS170: Tower of Hanoi click here
  - A tougher example of divide and conquer using recursion: click here (Not part of CS255 material)
- Tower of Hanoi in M68000 assembler code: click here (skipped for brevity - read through it yourself)
Programming project hw7 re-enforces recursion: click here
Working with linked lists:
- Remember how linked lists are stored inside the computer: click here
- Insert at start of the linked list: click here
- Insert a new element at the tail of the list:
  - Iterative algorithm to insert at tail of a list: click here --- skipped (just loop and if, you can read it)
  - Recursive algorithm to insert at tail of a list:
    - My CS171 material on the algorithm: click here
    - M68000 program: click here
- Insert into an ordered list: as hw8
Programming project hw8 re-enforces linked lists: click here

If you understand everything so far, you now know exactly what is going on when a computer executes a program. You can apply what you learn and write assembler programs in any assembler language, e.g., Intel Pentium, IBM PowerChip, DEC Alpha, SunMicrosystem SPARC... To program with a new chip, all you need to learn are:
I have SPARC and Intel material after the C lecture notes to demonstrate this process.

Introduction to the (System Programming Language) C for Java programmers

Introduction to C programming: click here
Things that are identical in Java and C: click here

Introduction to the C Pre-processor:

Intro: click here
Macros (#define): click here
Including files (#include): click here
Conditional compilation: click here
A trick to prevent a file being included multiple times: click here

C's data types and variables:

C's data types:

Overview: click here
Operations involving same and different data types: click here
Conversion rules in C: click here

The const modifier: click here

Basic input/output:

Printing values of the built-in data types: click here
Reading in values of the built-in data types: click here

Operators:

Arithmetic Operators: click here ( +, -, *, / )
Bit-wise-Operators:

The bit-wise operators: ( &, |, ^, ~ ) click here
How to use the bit-wise operators: click here
Denoting values in base 2, 8 and 16: click here
Bit manipulation functions - clear a bit, set a bit, flip a bit and test a bit: click here

Shift-Operators: click here ( >>, << )

Intro: click here
Set bit at position n: click here
Clear bit at position n: click here
Flip bit at position n: click here
Test bit at position n: click here

Assignment Operators: click here ( +=, -=, *=, /=, &=, |=, ~=, >>=, <<= )

Increment/decrement Operators: click here ( ++, -- )

Boolean data type and operations:

The Boolean data type in C: click here
Compare and Logic Operators: click here ( <, <=, >, >=, ==, !=, &&, ||, ! )

"Uncommon" operators:

The conditional operator ?: click here
The comma operator , click here
The sizeof operator click here

Priority and Associativity of the C operators click here

Statements:

Assignment Statement: click here
Selection Statements (if, if-else, switch): click here
Loop Statements (while, for, do-while): click here

Arrays:

Defining and using one-dimensional array variables: click here
Review: static and dynamic arrays: click here
Array bound checks: click here

Defining and using two-dimensional array variables: click here

"Bit" arrays: click here
Functions (methods):
- Intro to C Functions: click here
- Single file C program: Declaring functions:
  - Preliminary to function declaration:
    - Parameters/return values in a function call: click here
    - Correctness requirement on function call with mismatched (1) parameter type and (2) return value type: click here
    - Automatic conversion rules for function calls: click here
  - Important differences between the C and Java compilers:
    - One file vs. multi-file searching: click here
    - One-pass vs. two-pass compiler: click here
    - Implicit function prototyping in C: click here
  - Function declaration:
    - Function prototype --- declaring a function: click here
    - Removing the Implicit function prototyping in C: click here
    - The difference between defining and declaring a function in C: click here
- Multi-files C programs: the importance of declaring functions:
  - The simplest way to compile a multiple files C program: click here
  - The correct way to compile a multiple files C program: click here
  - The importance of function declaration in multi-file C programs: click here
  - Declaring function using header files: click here
- The make (UNIX) utility: (SKIP if time constrainted)
  - Specifying dependency between files --- makefiles: click here
  - The make utility: click here
  - Structure of makefiles: click here
  - Inference rules used in makefiles: click here
  - Macros in makefiles: click here
  - Miscellaneous makefile stuff (line continuation, comment, ...): click here
- The Parameter passing mechanism of C: click here
Hand out C Project 1: click here
Intermediate topics: things that look similar in C and Java but work differently
- Variables in C:
  - Kinds of variables in C: click here
  - Brief review: Life time and Scope of the variables: click here
  - Life time of variables in C: click here
  - Scope of variables in C:
    - Global variables:
      - Scoping rules for global variables in C: click here
      - Declaring global variables in C: click here
      - C Pre-processor trick to define and declare global variables: click here
    - Scoping rules for static global variables in C: click here
    - Scoping rules for static local variables in C: click here
    - Scoping rules for local and parameter variables in C: click here (pay attention !)
- More on arrays: declaring arrays and array as parameters of functions
  - Declaring array variables: click here
  - Functions with array parameters: click here
    - Declaring functions that have array parameters: click here
- Debugging a C program:
  - Using the gdb debugger: click here
Advanced datatypes
- Reference data type and reference (pointer) variables
  - Reference (pointer) data type and variables: click here
  - The reference (&) operator click here
  - Storing the result of reference (&) operator in reference data typed variables: click here
  - Using reference variables --- the dereference (*) operator: click here
  - How to read C's syntax for variable definition:
    - How to read "datatype *": click here
    - How to read "const": click here
  - Reference variables as parameters in a function (pass-by-reference): click here
  - Functions returning a reference : click here
  - The (type *) casting operator: click here
- User-defined types:
  - Structures:
    - Defining and using struct type and variables: click here
    - Declaring struct variables: click here
    - struct parameter variables: click here
    - Function that returns a struct: click here
    - Size of a struct "object": click here
  - Unions: click here
  - Enumeration types: click here
  - Bit fields structures: click here
  - Pointer to user-defined type (just add *): click here
  - The short-hand operator ->: click here
  - Passing user-defined typed variables "by reference": click here
  - C's typing mechanism: by (type) name equivalence: click here
  - typedef: defining a new name for a type (not defining a new type): click here
- How to create and maintain linked lists in C:
  - Review of linked lists and how to define linked list elements in C: click here
  - Introduction to linked lists in C: click here
  - Caveat: free deleted list elements !!! click here
  - Inserting and deleting at the head of a list:
    - Insert at head of list: click here
    - Delete at head of list: click here
  - Recursion: Inserting and deleting at the tail of a list: click here
  Hand out C Project 2: click here
- Pointer arithmetic and Arrays
  - Pointer arithmetic: click here
  - Accessing arrays with pointers : click here
  - Using pointer arithmetic to implement Dynamic arrays: click here
  - The [ ] operator: click here
  - Using the [ ] operator to implement Dynamic arrays: click here
  - The equivalance of pointers and arrays in C: click here
  - The ++ and -- operators used in pointer arithmetic: click here
- We have cover all operators !!. C's operators and their precedence: click here
- Strings in C --- arrays of char: click here
- Some Strings functions in C Standard library click here
- Array of Strings --- command line arguments: click here
Miscellaneous topics in C
- Special kinds of variables in C:
  - register variables: click here
- Function parameters:
  - Passing a function as a parameter to a function: click here
Hand out Homework 7 to re-inforce C++ programming click here

That's all, Folks !
Additional Enrichment Material: Intel 80x86 programming (not covered in CS255)
- A free Intel Macro Assembler (if you want to write assembler on your PC): RIGHT click here and SAVE AS
- An online documentation on Assembler programming with MASM: click here
- Intel Assembler Code Table: click here
- The Intel 80x86 CPU architecture: click here
- The Intel 80x86 directives: click here
- The Intel 80x86 Addressing modes: click here
- Arithmetic operations: click here
- Compare and Branch: click here
- Subroutine call and return: click here
- The Art of Assembler Language Programming book: click here
  Check out chapter 6
Rough notes on Intel Assemler programming:
- Intel registers: click here
- Intel registers: click here
- Reserving space for variables: click here
- Addressing modes (MOV): click here
- Arithmetic: click here
- CMP and Jump: click here
- Stack, procedure call/return: click here
Other resources:
- Matloff GNU assembler programming tutorial: click here
- Sourceforge GNU assembler programming tutorial: click here
- Free Intel Macro Assembler (if you want to write assembler on your PC): RIGHT click here and SAVE AS
- Intel Assembler Programming book - this book is like the CS255 course using Intel Assembler code: click here
- Step by step Windows programming tutorial shows you how to write window programs, menus, call backs, etc: click here
- The Art of Assembly Programming (a very good online book, but the 32 bit version uses a non-standard assembler called "HLA" - High Level Assemble language) click here