architecture, processor The sequence of actions that a
At the beginning of each cycle the CPU presents the value of
fetches the instruction from
main memory (possibly via a
From the instruction register, the data forming the
sends a sequence of control signals to the relevant
functionunits of the CPU to perform the actions required by the
instruction such as reading values from
registers, passing
them to the
ALU to add them together and writing the result
back to a register.
The program counter is then incremented to address the next
instruction and the cycle is repeated.
(1998-06-25)