Hardware register: Difference between revisions
mNo edit summary |
start conversion to active voice. |
||
Line 1: | Line 1: | ||
{{Unreferenced|date = October 2007}} |
{{Unreferenced|date = October 2007}} |
||
In [[digital electronics]], especially [[computing]], a '''hardware register''' stores bits of information, in a way that all the bits can be written to or read out simultaneously. |
|||
In [[computing]], a '''hardware register''' is a storage area for [[digital electronics]] and particularly [[computer hardware]] including the [[central processing unit]] (CPU) and [[input/output]] (I/O) of different kinds. Information is conditionally transferred between registers, sometimes with a functional transform, such as an [[Adder (electronics)|adder unit]]. |
|||
The hardware registers inside a [[central processing unit]] (CPU) are called [[processor register]]s. |
|||
Signals from a [[state machine]] to the register control when registers transmit to or accept information from other registers. |
|||
Sometimes the state machine routes information from one register through a functional transform, such as an [[Adder (electronics)|adder unit]], and then to another register that stores the results. |
|||
Typical uses of hardware registers include ''configuration'' and start-up of certain features, especially during initialization, ''buffer storage'' e.g. video memory for [[graphics card]]s, and ''status reporting'' such as whether a certain event has occurred in the hardware unit. |
Typical uses of hardware registers include ''configuration'' and start-up of certain features, especially during initialization, ''buffer storage'' e.g. video memory for [[graphics card]]s, and ''status reporting'' such as whether a certain event has occurred in the hardware unit. |
||
Line 7: | Line 10: | ||
Reading a hardware register involves accessing its memory- or port-address with a "load" or "store" instruction, issued by the processor. Hardware registers are addressed in words, but sometimes only use a few [[bit]]s of the word read in to, or written out to the register. |
Reading a hardware register involves accessing its memory- or port-address with a "load" or "store" instruction, issued by the processor. Hardware registers are addressed in words, but sometimes only use a few [[bit]]s of the word read in to, or written out to the register. |
||
'''Strobe registers''' |
'''Strobe registers''' have the same interface as normal hardware registers, but instead of storing data, they trigger an action each time they are written to (or, in rare cases, read from). They are a means of [[signaling (telecommunication)|signaling]]. |
||
== See also == |
== See also == |
Revision as of 04:38, 17 December 2007
In digital electronics, especially computing, a hardware register stores bits of information, in a way that all the bits can be written to or read out simultaneously. The hardware registers inside a central processing unit (CPU) are called processor registers. Signals from a state machine to the register control when registers transmit to or accept information from other registers. Sometimes the state machine routes information from one register through a functional transform, such as an adder unit, and then to another register that stores the results.
Typical uses of hardware registers include configuration and start-up of certain features, especially during initialization, buffer storage e.g. video memory for graphics cards, and status reporting such as whether a certain event has occurred in the hardware unit.
Reading a hardware register involves accessing its memory- or port-address with a "load" or "store" instruction, issued by the processor. Hardware registers are addressed in words, but sometimes only use a few bits of the word read in to, or written out to the register.
Strobe registers have the same interface as normal hardware registers, but instead of storing data, they trigger an action each time they are written to (or, in rare cases, read from). They are a means of signaling.