问题 单项选择题

若某计算机系统的I/O接口与主存采用统一编址,则输入输出操作是通过()指令来完成的。

A.控制

B.中断

C.输入输出

D.访存

答案

参考答案:D

解析:

[分析] 本题考查计算机系统中的输入输出系统基础知识。

常用的I/O接口编址方法有两种:一是与内存单元统一编址,二是单独编址。

与内存单元统一编址方式下,是将I/O接口中有关的寄存器或存储部件看作存储器单元,与主存中的存储单元统一编址。这样,内存地址和接口地址统一在一个公共的地址空间里,对I/O接口的访问就如同对主存单元的访问一样,可以用访问内存单元的指令访问I/O接口。

I/O接口单独编址是指通过设置单独的I/O地址空间,为接口中的有关寄存器或存储部件分配地址码,需要设置专门的I/O指令进行访问。这种编址方式的优点是不占用主存的地址空间,访问主存的指令和访问接口的指令不同,在程序中容易使用和辨认。

完形填空

However important we may regard school life to be, there is no denying the fact that children spend more time at home than in the classroom. Therefore, the great influence of parents cannot be ignored or discounted by the teacher. They can become strong allies of the school personnel or they can consciously or unconsciously hinder and frustrate curricular objectives.

Administrators have been aware of the need to keep parents informed of the newer methods used in schools. Many principles have conducted workshops explaining such matters as the reading readiness program, manuscript writing and developmental mathematics. Moreover, the classroom teacher, with the permission of the supervisors, can also play an important role in enlightening parents. The informal tea and the many interviews carried on during the year, as well as new ways of reporting pupils’ progress, can significantly aid in achieving a harmonious interplay between school and home.

To illustrate, suppose that a father has been drilling Junior in arithmetic processes night after night. In a friendly interview, the teacher can help the parent sublimate (升华) his natural paternal interest into productive channels. He might be persuaded to let Junior participate in discussing the family budget, buying the food, using a standard or measuring cup at home, setting the clock, calculating mileage on a trip and engaging in scores of other activities that have a mathematical basis.

If the father follows the advice, it is reasonable to assume that he will soon realize his son is making satisfactory progress in mathematics, and at the same time, enjoying the work. Too often, however, teachers’ conferences with parents are devoted to petty (不重要的) accounts of children’s misdeeds, complaints about laziness and poor work habits, and suggestion for penalties and rewards at home.

What is needed is a more creative approach in which the teacher, as a professional adviser, plants ideas in parents’ minds for the best utilization of the many hours that the child spends out of the classroom.

In this way, the school and the home join forces in fostering the fullest development of youngsters’ capacities.

(Note:Answer the questions or complete the statements with NO MORE THAN 14 WORDS)

小题1:Why do parents also have great influence on children?

_________________________________________________________________________ .

小题2:Through which ways can the teacher play an important role in enlightening parents?

_________________________________________________________________________ .

小题3:According to the teacher, that parents should let the boy ____________________________ if he wants to sublimate his natural paternal interest into productive channels in teaching his son arithmetic.

小题4:A more creative approach is needed for ___________________of children out of classroom.

判断题