Что (кто) такое instruction register - определение
Instruction register
REGISTER IN A CPU CONTROL UNIT HOLDING THE CURRENTLY-EXECUTING INSTRUCTION
In computing, the instruction register (IR) or current instruction register (CIR) is the part of a CPU's control unit that holds the instruction currently being executed or decoded. In simple processors, each instruction to be executed is loaded into the instruction register, which holds it while it is decoded, prepared and ultimately executed, which can take several steps.
Instruction Address Register
![Front panel of an [[IBM 701]] computer introduced in 1952. Lights in the middle display the contents of various registers. The '''instruction counter''' is at the lower left.](https://commons.wikimedia.org/wiki/Special:FilePath/IBM 701console.jpg?width=200 "Front panel of an [[IBM 701]] computer introduced in 1952. Lights in the middle display the contents of various registers. The '''instruction counter''' is at the lower left.")
PROCESSOR REGISTER THAT INDICATES THE LOCATION IN MEMORY OF THE CURRENTLY-EXECUTING INSTRUCTION IN THE BINARY CODE OF A PROGRAM
Instruction pointer; Program Counter; Program register; Instruction address register; Programme counter; Instruction counter; Next instruction pointer; Current instruction pointer; Current instruction; Next instruction; Next instruction address; Next instruction pointer register; Instruction pointer register; Next instruction address register
(IAR) The IBM name for program counter.
The IAR can be accessed by way of a supervisor call in
supervisor state, but cannot be directly addressed in
problem state.
(1995-03-21)
program counter
PROCESSOR REGISTER THAT INDICATES THE LOCATION IN MEMORY OF THE CURRENTLY-EXECUTING INSTRUCTION IN THE BINARY CODE OF A PROGRAM
Instruction pointer; Program Counter; Program register; Instruction address register; Programme counter; Instruction counter; Next instruction pointer; Current instruction pointer; Current instruction; Next instruction; Next instruction address; Next instruction pointer register; Instruction pointer register; Next instruction address register
<hardware> (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.
(1995-03-21)
