一、單項(xiàng)選擇題(本大題共20小題，每小題1分，共20分)

在每小題列出的四個(gè)備選項(xiàng)中只有一個(gè)是符合題目要求的，請(qǐng)將其代碼填寫在題后的括號(hào)內(nèi)。錯(cuò)選、多選或未選均無(wú)分。

1.端口編址采用隔離I/O方式的優(yōu)點(diǎn)是(      )

A.訪問存儲(chǔ)器的指令也能訪問I/O端口 

B.端口地址不占用存儲(chǔ)器地址空間

C.對(duì)I/O端口的編程靈活方便 

D.I/O指令類型少

2.串行通信，數(shù)據(jù)只能由A方傳到B方，這種通信方式稱為(      )

A.單工                                                         

B.半雙工 

C.全雙工                                                      

D.半雙工或全雙工

3.存放中斷號(hào)為60H的中斷向量的物理地址是(      )

A.240H~243H                                               

B.180H~183H  

C.240~243                                                    

D.180~183

4.當(dāng)代計(jì)算機(jī)（Pentium）采用更高速率的一種總線，足夠傳送新發(fā)展的快速數(shù)據(jù)業(yè)務(wù)，如圖像和視頻信號(hào)，此總線是(      )

A.ISA總線                                                   

B.PCI總線     

C.HOST總線                                                

D.USB總線

5.PC機(jī)可屏蔽硬件中斷中,鍵盤中斷的中斷號(hào)是(      )

A.06H                                                           

B.07H      

C.08H                                                           

D.09H

6.Pentium處理機(jī)的地址總線是32位的，其所能尋址的存儲(chǔ)器空間為(      )

A.20MB                                                        

B.4GB     

C.16GB                                                        

D.64GB

7.82C55 B口工作在方式1輸入，用程序控制方式讀取數(shù)據(jù)之前應(yīng)查詢(      )

A.PC₀                                                           

B.PC₁      

C.PC₂                                                           

D.PC₃

8.RS-449標(biāo)準(zhǔn)采用的連接器引腳數(shù)是(      )

A.9                                                               

B.25 

C.37                                                             

D.48

9.82C55 A口工作在方式1輸入，允許中斷，則輸出中斷請(qǐng)求信號(hào)的端子是(      )

A.PC₃                                                           

B.PC₄      

C.PC₅                                                           

D.PC₆

10.8250接口芯片的主要功能是(      )

A.僅完成串行數(shù)據(jù)到并行數(shù)據(jù)的轉(zhuǎn)換

B.僅完成并行數(shù)據(jù)到串行數(shù)據(jù)的轉(zhuǎn)換

C.發(fā)送時(shí)完成并-串轉(zhuǎn)換，接收時(shí)完成串-并轉(zhuǎn)換

D.發(fā)送時(shí)完成串-并轉(zhuǎn)換，接收時(shí)完成并-串轉(zhuǎn)換