Organization n301.tplt Chapter 5 Computer Organization Levels of Abstraction Still hardware At a component (subsystem) level

• transistors -->gates -->circuits
• circuits -->subsystems

Abstraction hides detail

• important concept in my areas of CS

Von Neumann architecture Four major subsystems

• memory
• input/output (I/O)
• arithmetic-logic unit (ALU)
• control unit

Stored program concept Sequential fetch-execute cycle