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所有磁盘和磁鼓都包含一个旋转的磁记录面和靠近磁记录面的读头和写头。不同的只是在旋转介质的外形和结构以及磁头的定位方面有差别。信息以磁化方式记录在旋转表面的位串(一次一位)磁道上。在不影响磁盘的剩余部分的情况下,每个磁道都可以修改。高的旋转速度和闭包数据提供数据记录和读出速率(传递速率)高达每秒几百万8位字符。磁鼓具有一个外形为鼓状的记录面和许多密封于防护壳内的固定磁头(如图1)。每个磁头对应于一个数据磁道。磁鼓的存贮容量范围为从9万到2千万以上的8位字符。由于磁头是固定的,因此平均存取时间直接依赖于记录表面介质的旋转速度,也就是说,所需要的数据块开始移到磁头下面所需的时间是相当快的,一般是5到15毫秒。
All disks and drums contain a rotating magnetic recording surface and a read-head and write-head near the magnetic recording surface. The difference is only in terms of the shape and structure of the rotating medium and the positioning of the head. The information is magnetically recorded on the bit string (one bit at a time) of the rotating surface. Without affecting the rest of the disk, each track can be modified. High spin speed and closure data provide data logging and read rates (transfer rates) up to millions of 8-bit characters per second. The drum has a drum-shaped recording surface and a number of fixed magnetic heads sealed in the housing (Figure 1). Each head corresponds to a data track. The drum storage capacity ranges from 90,000 to more than 20 million 8-bit characters. Since the heads are stationary, the average access time is directly dependent on the speed of rotation of the recording surface media, that is, the time required to start moving the desired blocks of data below the heads is quite fast, typically 5 to 15 milliseconds .