What Is a Register File ?

A register file is a means of memory storage within a computer's central processing unit (CPU). The computer's register files contain bits of data and mapping locations. These locations specify certain addresses that are input components of a register file. Other inputs include data, a read and write function and execute function.

When a user installs a program on a computer, that software application writes a register file on the CPU. Most software programs will contain more than one file. Those files contain execution instructions that the CPU follows when the user launches and uses the application. A register file also lets the CPU know where program is located and what data is needed to perform certain functions.

Decoders are a part of a register file. When data is extracted from a register, the computer's hard drive refers back to the bits that are contained in the file. Part of the extraction process involves reading and deciphering the data bits that are contained in the register. Once a program completes a function, it may write a code or message indicating the results of the operation. 

Register files utilize one of two technologies related to memory. The first is known as static random access memory, or SRAM. With static random access memory there are several bits of memory that are labeled according to binary code. The status of each memory bit is labeled with a zero or one, indicating an active or inactive state.

A second type of register memory is dynamic random access memory, or DRAM. Each section of memory contains a capacitor and transistor. Data values are equated with different charges and must be constantly updated by the memory chip. The update or "refreshing" will typically take up to 2 percent of the total processing time.

There are two components to the memory chip's ability to process data. They include cycle and access time. The cycle time is the lowest amount of time that occurs between data requests. Access time is the amount of seconds or minutes it takes for the CPU to request data from a register file and the time it takes to actually receive that information. 

While SRAM is usually used with memory caches, its cycle time and access time are the same. With DRAM technology, the cycle time is typically longer than its access time. This is because memory reads or extractions involve a destroy and re-write process.