1 / 6

Register

Register.

bette
Télécharger la présentation

Register

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Register Registers are normally measured by the number of bits they can hold, for example, an "8-bit register" or a "32-bit register". Registers are now usually implemented as a register file, but they have also been implemented using individual flip-flops, high speed core memory, thin film memory, and other ways in various machines.

  2. Types of Registers A processor often contains several kinds of registers, that can be classified according to their content or instructions that operate on them: • User-accessible Registers - The most common division of user-accessible registers is into data registers and address registers. • Data registers are used to hold numeric values such as integer and floating-point values. In some older and low end CPUs, a special data register, known as the accumulator, is used implicitly for many operations.

  3. Types of registers • Address registers hold addresses and are used by instructions that indirectly access memory. In some CPUs, a special address register is an index register, although often these hold numbers used to modify addresses rather than holding addresses.

  4. Types of Registers • Conditional registers hold truth values often used to determine whether some instruction should or should not be executed. • General purpose registers (GPRs) can store both data and addresses, i.e., they are combined Data/Address registers. • Floating point registers (FPRs) store floating point numbers in many architectures.

  5. Types of Registers • Constant registers hold read-only values such as zero, one, or pi. • Vector registers hold data for vector processing done by SIMD instructions (Single Instruction, Multiple Data). • Special purpose registers hold program state; they usually include the program counter (aka instruction pointer), stack pointer, and status register (aka processor status word). • Instruction registers store the instruction currently being executed. • Index registers are used for modifying operand addresses during the run of a program.

  6. Types of Registers • In some architectures, model-specific registers (also called machine-specific registers) store data and settings related to the processor itself. Because their meanings are attached to the design of a specific processor, they cannot be expected to remain standard between processor generations. • Control and status registers - It has three types. Program counter, instruction registers, Program status word (PSW). • Registers related to fetching information from RAM, a collection of storage registers located on separate chips from the CPU (unlike most of the above, these are generally not architectural registers): • Memory buffer register • Memory data register • Memory address register • Memory Type Range Registers

More Related