第二章 Hardware Component.ppt

Lesson One the Central Processing Unit The CPU stands for Central Processing Unit. The CPU coordinates all the activities of the various components of the computer .It determines which operations should be carried out and in what order. The CPU can also retrieve information form memory and store the results of manipulations back into the memory unit for later reference. coordinate vt.调整，整理 activity n.活跃，行动 various adj.各种各样的 determine v.决定，确定 operation n.操作，运转 carry out 执行 order n.顺序，命令；v.命令 retrieve n.找回；v.重新得到 reference n.提及，参考 The processor contains four key components: a clock, an instruction control unit, an arithmetic and logic unit, and a set of registers. The speed at which the CPU operates is called the clock speed and is measured in megahertz (MHz). A clock cycle is the time that the CPU takes to perform instructions at a given clock speed. Clock cycles are measured in nanoseconds (ns). a clock 一个时钟 instruction control unit 指令控制单元 arithmetic and logic unit 算术逻辑单元 register 寄存器 megahertz 兆赫 clock cycle 时钟周期 Nanoseconds 纳秒 The arithmetic and logic unit executes that instruction. It consists of the circuits that add, subtract, multiply, divide, compare, copy, and initiate input or output the computer’s instruction set. Registers are temporary storage devices that hold control information, key data, and intermediate results. Subtract 减去 Multiply 乘，繁殖 Divide 除 Compare 比较 initiate 开始 intermediate result 中间结果 When you buy a PC or a CPU, you must pay attention to some indexes of the CPU. Main frequency or internal frequency: External frequency: CPU ratio: 英语口语练习材料 1.Asking a woman‘s age is impolite in my country.?? 在我们国家，问女士的年龄不礼貌的。 2.Meeting new people makes me nervous.?? 与陌生人见面使我很紧张。 3.Working hard will produce good results.?? 努力工作将产生好结果。 4.Making money is everybodys