Computer Architecture and Organization Prelim 1

Computer programming language

Expresses a set of detailed instructions or standard form of commands, containing unique keywords and syntax, which are compiled to perform a specific task by the central processing unit (CPU) of a computer.

Low-Level Languages

These are programming languages that deal with a computer's hardware components and constraints, and work to manage a computer's operational semantics.

Assembly language

It is a low-level language that uses short human-readable instructions, also known as mnemonic codes, which allow programmers to introduce names for block of memory that hold data.

Machine language

It is a low-level language composed of a set of executable instructions that are in binary formal, also known as numeric code. Machine language is also referred to as machine code.

High-Level Languages

These are programming languages that enable program development through user-friendly programming context, which are generally independent of the computer's hardware architecture.

Compiler

A computer software that translates (compiles) source codes written in high-level language into a set of low-level language instructions that can be understood by a computer's CPU. The formal output of the compilation process is called object code or object module.

Scanning

Reads the characters in the source code, from left to right, and groups it to have a collective meaning

Lexical Analysis

The compiler converts the groups of characters into series of characters known as tokens. Tokens are characterized by regular expressions which can be recognized and understood by a lexical analyzer.

Syntactic Analysis

The compiler checks the proper arrangement of the tokens as per their usage in the corresponding source code grammar. Syntax pertains to the correct order of a set of tokens, or sometimes referred to as keywords, that leads to the desired results.

Assembler

It is a program that translates assembly language into machine codes that can be executed by the computer. This bridges the symbolically coded instructions written in assembly language and the computer processor, including memory and other computational components, by assembling and converting assembly codes into object codes that are composed of zeros and ones.

Semantic Analysis

This phase involves several intermediate processes. In general, this examines whether the constructed parse tree complies with the rules of the language.

Object Code

It is the machine language representation of a programming source code wherein it encompasses a sequence of statements in binary form that are generated after compiling a particular source program. It is the output file or program of a compiler or an assembler which can then be transformed to another executable form by a linker.

Linker

It is a utility program that combines one (1) or more object files from separately compiled programs into a single file containing loadable or executable codes. The major tasks of a linker are to search and locate reference modules or routines in a program, and to determine the memory location where the codes will be loaded.

Executable Code

It is the output file, or program, of a linker that indicates tasks according to the encoded instructions the central processing unit (CPU) can directly execute.

Loader

A a major part of an operating system that is responsible for loading executable files, including libraries, into the memory and executes them.

Translator

It is the general term for a programming language processor that converts a computer program from one (1) language to another. It takes a program written in source code and converts it into machine code. There are three (3) types of translator: the compiler, interpreter, and assembler.

Processor

An integrated electronic circuit that performs the calculations that runs a computer.

Control Unit (CU)

This manages the overall operation of the processor. It controls the movement of data and instructions in and out of the device, including the operation of the arithmetic logic unit.

Arithmetic Logic Unit (ALU)

This is a combinational circuit that executes the actual computations and bit manipulation operations in a processor under the direction of the control unit.

Register Set

This is a temporary internal storage that serves as source and destination locations for instruction operations.

Fetch instruction

The processor reads the instruction from memory, which can be a register, cache, or the main memory.

Interpret instruction

The instruction is decoded to determine required actions.

Fetch data

The execution of an instruction may require reading data from memory or an input/output (I/O) module.

Process data

The execution of an instruction may require some arithmetic or logical operation on data.

Write data

The result of an execution may require writing data to memory or an I/O module.

Bit

A bit is the smallest unit of information in a digital computer. It represents a discrete data element containing the value zero (0) or one (1).

Byte

Composed of eight bits placed together to form a single value. It is the smallest unit of information that can be read from or write to a computer memory by most modern processors.

Positional number system

The ultimate numeric value is determined by the position the number holds, and not by the number itself. The placement of digits works through the use of a base number with a series of exponents applied to the base.

Binary number system

Also known as the base-2 number system, is a system that represents counting numbers by using the numerals 0 and 1.

Hexadecimal number system

Also known as the base-16 number system, encompasses binary numbers that are separated into groups of 4bits.

1's complement

The only process involved in this operation is the inversion of the given binary number. This operation is seldomly used for representing signed (positive or negative) binary numbers since, 010 has two representations in 1's complement which are: -010 that is represented with 1s (e.g., 111112 in a 5-bit register); and +010 that is represented with 0s (e.g., 000002 in a 5-bit register). Example: The 1's complement of 1001 0011 is 0110 1100.

2's complement

The processes involved in this operation are the inversion of the given binary number and the addition of 1 to the LSB. This operation is highly utilized in representing signed (positive or negative) binary numbers.