Computer Architecture

System Software Tools

Editor - makes changes as commanded by user
Assembler - used to write system as well as application program
- translate a program from assembly language source to object code that is very close to machine code
Compiler - translate another p[program from a high - level language to object code
Linkers - application is written in C the other part can be written in assembly
Loader - only an executable file may be loaded into memory before its execution
- loading function is performed by a routine in the OS known as the loader
Debugger - when a program first execute on the the computer, it may not work correctly as expected

Registers

Accumulator (AX register) - is a register in which intermediate arithmetic and logic results are stored. Without a register like an accumulator, it would be necessary to write the result of each calculation (addition, multiplication, shift, etc.) to main memory, perhaps only to be read right back again for use in the next operation.