Computer Architecture is defined as the attributes having a direct impact on the logical execution of a computer. It is also defined as a specification featuring how a set of software and hardware interact. It involves the design of the computer system. Also, computer architecture defines the structure and function of a variable component of a computer system. Some of the examples of computer architecture are instruction set, I/O mechanisms, memory addressing techniques, etc.
How do you define computer structure?
There are many components of the computer (like registers, arithmetic logic unit, control unit, and CPU interconnection). Therefore, the computer structure is defined as the way in which the mentioned components are interrelated. There are major four types of structural components of the computer system. They are termed as main memory, CPU, I/O and O/P, and system interconnection. The memory consists of various data and instruction.The central processing unit consists of various control and status register. They are memory buffer register, the memory address register, instruction register, instruction buffer register, and program counter. The I/O module is needed for various purposes like data buffering, error detection, device communication and so on. Some of the examples of I/O module are MODEM, speaker, disk, monitor, etc.
The memory buffer register contains a sequence of words to be stored in the main memory. The memory address register specifies the address in the main memory. Similarly, the instruction register contains 8-bit machine language instruction to be executed whereas the instruction buffer register holds the instruction from a sequence of word temporarily. And, the program counter consists of the address of the next instruction to receive from the main memory.
The above-mentioned memory address register and the memory buffer register are used to exchange data with memory in the central processing unit (CPU). The data and instruction in the main memory contain a binary number that signifies a sequence of words. The main function of I/O address register is to specify a desired I/O device. To exchange various information (data and instruction) between I/O and CPU; the I/O buffer register is used.
The operations like data storage, data processing, data movement, and control are carried out by the above-mentioned structural components. Memory cells are required for storing the data information because the data storage operation is carried out by the memory cells.
Similarly, data processing is done by various logic gates. The data processing operation may be arithmetic as well as logic.
The arithmetic operation means to add, subtract, divide, multiply, etc. And, the logical operation is based on the Boolean operation.
Also, the paths between the components are used for data movement operation. In data movement, various data is moved from or to the main memory via gates. And, the control operation is done by the control units where the paths between various components are needed to carry control signals.
Hence, the main component of the computer system is arithmetic and logic unit, control unit, I/O and computer memory. The control unit, in fact, controls the data storage facility and data processing facility. And, the presence of data movement apparatus plays an important role in working the system by playing a bridge role between control mechanisms and operating environment.