gates and circuits operate on the most elemental type of data: binary 0's and 1's
people typically work with mroe complex units of info such as decimals, chars, variables,and isntructions
to figure out how computers proccess this info, we must look at higher-level components than gates and circuits
computer organization - the branch of cs that studies computers in terms of their major functional units
Von Neumann Archiecture - single theoretical model that all modern computers are base on
4 major sybsystems - memory, input/output, arithmetic/logic unit (ALU), and control unit
ALU = control unit = CPU (Central Proccessing Unit)
stored program concept - instructions are executed by the computer in the form of binary units and stored in memory
sequential execution of instructions - instructions are fetched at a time from memory and passed to the control unit when decoded and executed
Memory and Cache
memory - functional unit of a computer that stores and retrieves instructions and data
random access memory- a memory unit where memory is divided into fixed sized units (cells) and all accesses to memory are given a specific address
Read only memory (ROM) - a type of random access memory which info has been prerecorded during manufacture
cache memory - special high speed memory that stores data that will probably be accessed in the near future to speed up the retrival of data
unit that allows a computer tpo communicate and interact with outside world and store info long term
volatile memory - info that dissapears when computer is powered off
non-volatile memory - info saved between shutdown of machines
DASD memory - memory type where every unit of info has a unique address but time for retrival of data depends on address' physical location and the current state of the device
SASD memory - memory that does not require for all units of data to be assigned a unique address
subsystem that performs mathematical and logical operations
made up of three parts: register, interconnections between componenents, and ALU circutry
register - special high-speed storage cell that contains the operands of an arithmetic operation and also sotres the result
sotred program - sequence of machine language instructions sotred as binary values in memory
fetches from memoy the next instruction to be executed and decodes it
execudes instructions by issueing the appropirate command to ALU, Memory, or I/O controls
Schneider, G. Michael, and Judith L. Gersting. Invitation to Computer Science. Cengage Learning, 2019