ABB TP854 3BSE025349R1 输入模块

ABB TP854 3BSE025349R1  输入模块

访问存储器中一个特定位置所需的时间。相关的测量单位通常是十亿分之一秒对于主存储，毫秒用于二级存储，以及第二用于三级存储。将读取等待时间和写入等待时间分开(特别是对于非易失性存储器)以及在顺序存取存储的情况下，最小、最大和平均等待时间是有意义的。从存储器中读取信息或向存储器中写入信息的速率。在计算机数据存储中，吞吐量通常用每秒兆字节(MB/s)来表示比特率也可以使用。与延迟一样，可能需要区分读取速率和写入速率。此外，顺序访问介质(而不是随机访问)通常会产生最大的吞吐量。存储信息的紧凑性。它是介质的存储容量除以长度、面积或体积的单位(如每平方英寸1.2兆字节)。基于存储在那里的(部分)内容来选择每个可单独访问的信息单元。内容寻址存储可以使用软件(计算机程序)或五金器具(计算机设备)，硬件速度更快，但价格更高。硬件内容可寻址存储器通常用于计算机的CPU缓存。

使用半导体基于集成电路储存信息的芯片。数据通常存储在金属-氧化物-半导体(MOS)存储单元。一个半导体存储芯片可能包含数百万个存储单元，由微小的金属氧化物半导体场效应晶体管(MOSFETs)和/或MOS电容。两者不稳定的和非易失性的存在多种形式的半导体存储器，前者使用标准MOSFETs，后者使用浮栅MOSFETs。在现代计算机中，主存储器几乎完全由动态易失性半导体组成随机存取存储器(内存)，特别是动态随机存取存储器(DRAM)。世纪之交以来，一种非挥发性的浮动栅半导体存储器被称为闪存作为家用计算机的离线存储器，已经稳步获得了市场份额。非易失性半导体存储器也用于各种高级电子设备和为其设计的专用计算机中的辅助存储。使用不同的模式磁化在一个有磁力地储存信息的涂层表面。磁性存储器是非易失性的。使用一个或多个可包含一个或多个记录传感器的读/写头来访问信息。读/写头仅覆盖表面的一部分，因此为了访问数据，头或介质或两者必须相对于另一个移动。在现代计算机中，磁存储将采取以下形式

ABB TP854 3BSE025349R1  输入模块

The time required to access a specific location in memory. The relevant units of measurement are usually billionths of a second for primary storage, milliseconds for secondary storage, and second for tertiary storage. It makes sense to separate the read latency from the write latency (especially for nonvolatile memory) and in the case of sequential access storage, the minimum, maximum and average latency. The rate at which information is read from or written to memory. In computer data storage, throughput is usually expressed in megabytes per second (MB/s), and bit rate can also be used. As with latency, it may be necessary to distinguish between read rate and write rate. In addition, sequential access to media (rather than random access) usually produces the maximum throughput. The compactness of stored information. It is the storage capacity of a medium divided by the length, area or volume (for example, 1.2 megabytes per square inch). Each individually accessible information unit is selected based on the (partial) content stored there. Content addressable storage can use software (computer program) or hardware (computer equipment), which is faster but more expensive. Hardware content addressable memory is usually used for CPU cache of computers.

A chip that uses semiconductors to store information based on integrated circuits. Data is usually stored in metal-oxide-semiconductor (MOS) memory cells. A semiconductor memory chip may contain millions of memory cells, which are composed of tiny metal oxide semiconductor field effect transistors (MOSFETs) and/or MOS capacitors. There are many forms of semiconductor memories, both of which are unstable and nonvolatile. The former uses standard MOSFETs and the latter uses floating-gate MOSFETs. In modern computers, the main memory is almost entirely composed of dynamic volatile semiconductors, random access memory (RAM), especially dynamic random access memory (DRAM). Since the turn of the century, a nonvolatile floating gate semiconductor memory called flash memory has steadily gained market share as an off-line memory for home computers. Non-volatile semiconductor memories are also used for auxiliary storage in various advanced electronic devices and special computers designed for them. Using different modes to magnetize on a coating surface that magnetically stores information. Magnetic memory is non-volatile. Information is accessed using one or more read/write heads, which may include one or more recording sensors. The read/write head covers only a part of the surface, so in order to access data, the head or the medium or both must move relative to the other. In modern computers, magnetic storage will take the following forms.