•A bus is a collection of wires carrying information with a common purpose.
•For each read or write operation, the CPU specifies the location of the data or instruction by placing an address on the address bus, then
activates a signal on the control bus indicating
whether the operation is read or
write.
•Read operations retrieve a byte of data from memory at the location specified and place it on the data bus. CPU reads the data and places it in
one of its internal registers.
•Write operations put data from CPU on the data bus and store it in the location specified.