List of five important instruction set design issues

The following are the most important fundamental design issues in instruction design.

(i) Operation Repertoire : This issue is concerned with how many and which operations are to be provided, and how complex operations should be

(ii) Data Types : This issue deals with the various types of data upon which operations are performed.

(iii) Instruction Format : This issue is concerned with instruction length (in bits), number of addresses, size of various fields and so on.

(iv) Registers : This is concerned with the number of registers that can be referenced by instructions, and their use.

(v Addressing: This issue is concerned with the mode or modes by which the address of an operand is specified.

These fundamental issues are interrelated with each other and so they must be considered together while designing an instruction set.

Operation repertoire: How many and which operations to provide, and how complex operations should be
Data types: The various types of data upon which operations are performed
Instruction format: Instruction length (in bits), number of addresses, size of various fields, and so on.
Registers: Number of CPU registers that can be referenced by instructions, and their use.
Addressing: The mode or modes by which the address of an operand is specified