Address bus - Citizendia

An address bus is a computer bus, used by CPUs or DMA-capable units for communicating the physical addresses of computer memory elements/locations that the requesting unit wants to access (read/write). In Computer architecture, a bus is a subsystem that transfers data between computer components inside a Computer or between computers Direct memory access ( DMA) is a feature of modern Computers and Microprocessors that allows certain hardware subsystems within the computer to access system

The width of an address bus, along with the size of addressable memory elements, determines how much memory can be accessed. For example, a 16-bit wide address bus (commonly used in the 8-bit processors of the 1970s and early 1980s) reaches across 2¹⁶ = 65,536 = 64 Ki memory locations, whereas a 32-bit address bus (common in PC processors as of 2004) can address 2³² = 4,294,967,296 = 4 Gi locations. Eight-bit CPUs normally use an 8-bit data bus and a 16-bit address bus which means that their Address space is limited to 64 KBs This is not a "natural The range of Integer values that can be stored in 32 bits is 0 through 4294967295 or −2147483648 through 2147483647 using Two's complement encoding "MMIV" redirects here For the Modest Mouse album see " Baron von Bullshit Rides Again " In computing binary prefixes are names or associated symbols that can precede a unit of measure (such as a Byte) to indicate multiplication by a power of two

In most microcomputers such addressable "locations" are 8-bit bytes. microcomputer is a Computer with a Microprocessor as its Central processing unit. A byte (pronounced "bite" baɪt is the basic unit of measurement of information storage in Computer science. In such case the above examples translate to 64 kibibytes (KiB) and 4 gibibytes (GiB) respectively. A kibibyte (a contraction of ki lo bi nary byte) is a unit of Information or Computer storage, established by the International A gibibyte (a contraction of gi ga bi nary byte) is a unit of Information or Computer storage, abbreviated GiB. Historically, there were also some examples of computers, which were able to address only areas of a larger size (words), such as 16, 32, 36 bits long.

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