CS-01 Computer Fundamentals
Hints For Revision
Block II
Instruction set – It is a collection of all the instructions that a CPU can execute.
Elements
of an instruction
- An opcode, which specifies the operation to be performed.
- A reference to the operands which may store the results of data processing operation by the instruction.
- A reference to the operands on which data processing is to be performed.
- A reference for the next instruction, to be fetched and executed.
Types
of instructions
- Data Processing Instructions
- Data Storage/Retrieval Instructions
- Data Movement Instructions
- Control Instructions
- Miscellaneous Instructions
Operand
Data Types – These data types specify the type
of data on which a particular operation is to be performed. These are
addresses, numbers, characters and logical data.
Types of operation
- Data Transfer operations
- Arithmetic operations
- Logical and Shift operations
- Conversion operations
- Input/output operations
- System control operations
- Transfer of control operations
Subroutine
call
Addressing
schemes - It refers to the mechanism employed
for specifying operands.
Types
of addressing schemes
- Immediate addressing
- Direct Addressing
- Indirect Addressing
- Register Addressing
- Register Indirect Addressing
- Displacement Addressing
- Stack Addressing Scheme
Some
common registers
- Accumulator (AC)
- Data Register (DR)
- Program Counter (PC)
- Instruction Register (IR)
- Memory Address Register (MAR)
Micro-operations - It is an action performed by a machine on the data stored in the registers.
There are four types of micro-operations:
- Register transfer micro-operations
- Arithmetic micro-operations
- Logic micro-operations
- Shift micro-operations
Arithmetic
Processors, Peripheral Processor
and Coprocessors
Wilkes
Control - In Wilkes design, a microinstruction
has two major components:
- Control field
- Address field
Microinstruction – It is an instruction of a microprogram.
Types
of microinstructions – Branching and non-branching
Microinstruction
formats – Horizontal microinstruction and vertical
microinstruction
Microinstruction
Sequencing
Block III
CPU
Registers
- Segment Registers
- Pointer and Index Registers
- Special Registers
- Flags Registers
Addressing
Modes
- Register
- Immediate
- Memory
Input/Output
Services - Interrupts
