Essay On Computer Architecture And Organization

Computer Architecture and Organisation is the study of the internal functions, procedures, structuring and implementation of a computer system. Computer Architecture refers to a catalogue of tools that are made available for users of a system. In other words, computer architecture is an abstract model of computer system which includes a set of computer resources like general purpose registers, program status word, instruction set and other features such as address space. It also refers to the externally visual attributes of the computer system. Generally, externally visual attribute is the way a system is visible to the logic of programs (not the human eyes!), whereas the organisation of a computer system refers to the logical structure of the system, including CPU,

ii. Memory Write Operation:
The transfer of new information to be stored into the memory is called memory write operation. The particular memory word is selected by the memory address during the transfer. It is necessary to specify the address of M when writing memory operations this is done by including the address in square brackets following the letter M.
Steps for the data to be read from memory
1. Processor signals the memory location to be written by placing the memory address onto the address bus.
2. Processor places the data to be written onto the data bus.
3. Specific memory chips that hold memory locations are ready and selected.
4. Delay is added to allow memory to be available to write.
5. Control unit of processor turns on the write line of the control bus.
6. Data is written to the correct memory location.
For example:
Write: M[AR] R1
Memory write causes a transfer of information into DR from the memory word M selected by the address in AR. The input data is in register R1 and address in AR.
Timing diagram of memory read operation: Figure1.1.10: Memory Write (Timing