program counter

program counter

A register in the control unit of the CPU that is used to keep track of the address of the current or next instruction. Typically, the program counter is advanced to the next instruction, and then the current instruction is executed. Also known as a "sequence control register" and the "instruction pointer." See address register and instruction register.

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program counter [′prō·grəm ‚kau̇nt·ər]

(computer science)

instruction counter

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(hardware)

program counter - (PC, or "instruction address register") A register in the central processing unit that contains the addresss of the next instruction to be executed. The PC is automatically incremented after each instruction is fetched to point to the following instruction. It is not normally manipulated like an ordinary register but instead, special instructions are provided to alter the flow of control by writing a new value to the PC, e.g. JUMP, CALL, RTS.