Instruction cycle and interrupts.

Processor

• Controls the operation of the computer andperforms its data processing functions

• Stores data andprograms

• Move data between the computer andits external environment.– for communication among processors,main memory, and I/O modules.e.g. secondary memory devices (disks),communications equipment, terminals

• – for communication among processors,main memory, and I/O modules.

Memory

• Controls the operation of the computer andperforms its data processing functions

• Stores data and programs

• Move data between the computer andits external environment.– for communication among processors,main memory, and I/O modules.e.g. secondary memory devices (disks),communications equipment, terminals

• – for communication among processors,main memory, and I/O modules.

I/O modules

• Controls the operation of the computer andperforms its data processing functions

• Stores data and programs

• Move data between the computer andits external environment.– for communication among processors,main memory, and I/O modules.e.g. secondary memory devices (disks),communications equipment, terminals

• – for communication among processors,main memory, and I/O modules.

System Bus

• Controls the operation of the computer andperforms its data processing functions

• Stores data and programs

• Move data between the computer andits external environment.– for communication among processors,main memory, and I/O modules.e.g. secondary memory devices (disks),communications equipment, terminals

• – for communication among processors,main memory, and I/O modules.

Memory address register (MAR)

• Specifies the address in memory for the next read or write

• contains the data to be writteninto memory or receives the dataread from memory

• specifies a particular I/O device

• used for the exchange of data between an I/O moduleand the processor

Memory buffer register (MBR)

• Specifies the address in memory for the next read or write

• contains the data to be writteninto memory or receives the dataread from memory

• specifies a particular I/O device

• used for the exchange of data between an I/O moduleand the processor

I/O address register (I/OAR)

• Specifies the address in memory for the next read or write

• contains the data to be writteninto memory or receives the dataread from memory

• specifies a particular I/O device

• used for the exchange of data between an I/O moduleand the processor

I/O buffer register (I/OBR)

• Specifies the address in memory for the next read or write

• contains the data to be writteninto memory or receives the dataread from memory

• specifies a particular I/O device

• used for the exchange of data between an I/O moduleand the processor

______ consists of a set of locations, defined by Sequentially numbered addresses.Each location contains a bit pattern that can be interpreted as either an instruction or data.

______ transfers data from external devices to processor and memory, and vice versa.It contains internal buffers for temporarily holding data until they can be sent on