问题 单项选择题

变址寻址和基址寻址的有效地址形成方式类似,但()。

A.变址寄存器的内容在程序执行过程中是不能改变的

B.基址寄存器的内容在程序执行过程中是可以改变的

C.在程序执行过程牛,变址寄存器的内容不能改变而基址寄存器的内容可变

D.在程序执行过程中,基址寄存器的内容不能改变而变址寄存器的内容可变

答案

参考答案:D

解析:

从计算操作数的有效地址的方法上来看,变址寻址和基址寻址是相似的,都是把某个寄存器的内容加上指令字中的形式地址而形成操作数的有效地址。实际上,两者有着不同的特点和用途。首先,在采用了基址寻址的计算机系统中,基址是不变的,程序中的所有地址都是相对于基址来变化的。而对于变址寻址来说则相反,指令中的地址字段的形式地址给出的是一个存储器地址基准,变址寄存器X中存放的是相对于该基准地址的偏移量。不同的变址寄存器值指向不同的单元。第二,在基址寻址中,偏移量倍数较小,而在变址寻址中,偏移量倍数足以表示整个存储空间。第三,基址寻址是解决程序逻辑空间与存储器物理空间的无关性,而变址寻址主要是为了编写出高效访问一片存储空间的程序。

完形填空

信息匹配:(共5小题,每题2分,满分10分)

下面是一篇应用文及其应用场合的信息,请阅读下列应用文和相关信息,并按照要求匹配信息。选项中有一项是多余的。

首先,请阅读下列广告语:

A. “Just do it!” — This slogan (口号) speaks out to teens. It tells them to do something, but only if they think it’s worth it. And if so, why not do it wearing Nike?

B. “Always Coca-Cola.”— Coke’s slogans change every few years, but this one has enjoyed a lasting popularity because it shows the brand’s spirit. It seems to say “Coke is the only drink there is; there are no other forms of drink.”

C. “Share moments, share life.” — This slogan from Kodak connects photos and beauty. It asks people to remember the happy moments in life by taking photos of them — using Kodak film of course!

D. On hearing the slogan “Make yourself heard”, you will know there is Ericsson product for you to call anyone.

E. There are some public service advertisements (PSAs) that educate people about public service projects, such as Project Hope. Its slogan is “Project Hope(希望工程) — Schooling every child.”

F. One toothpaste ad says “Bright-teeth fights bad breath!” The advertisers want you to read the word “fight” and think that the toothpaste cures bad breath.

请阅读以下购买者的信息,然后匹配购买者和他/她拟购买产品的广告语:

Jack passed the entrance exam and was admitted to a famous university. These days, his father is looking for a mobile phone for him so as to keep in touch with each other closely. 

Tom was a senior middle school student. He likes sports very much and plays football every afternoon. But after class this afternoon he has to buy a pair of shoes because his shoes have been worn out.

There’s a party this evening — for Mary’s 15th birthday. Her family are making preparations for it. Her brother’s job is to buy some drink.

Joan doesn’t want to forget the past, especially the happy moments.

Alice is afraid of opening her mouth, because a bad smell will come out, which makes her feel embarrassed when talking with others. So she needs something which can remove the smell no matter how much it is.    

购买者                      广告语

51. Jack                            A. Just do it!

52. Tom                         B. Always Coca-Cola.

53. Mary                        C. Share moments, share life.

54. Joan                            D. Make yourself heard. 

55. Alice                       E. Project Hope — Schooling every  child.

F. Bright-teeth fights bad breath!

单项选择题 A1型题