计算机专业英语习题+答案

习题+答案

2.1

Write T or F to each stateme nt

T6. An asynchronous device is a clocked device.

T7. A latch is an asynchronous device, because it functions at arbitrary times.

T8. The repetiti on of clock pulse can vary from very low rate to very high rate.

T9. A synchronous device changes its state only on the arrival of a clock pulse.

F10. A clock in put may occur at any time.

T11. The clock pulses are used to synchronize all operations of the shift register.

T13. A uni direct ional shift register is capable of shift ing in one direct ion only.

F14. I n a shift-left register the serial in put determ ines what goes into the leftmost position during the shift register.

F15. To provide parallel tran sfer capability some additi onal in put and output lines should be provided to the shift register.

Choose the best an swer for each of the follow ing

1. How can the output of a logic gate be en ergized? C

A By cha nging its in puts.

B By rema ining its in puts un cha nged.

C By meet ing the specific in put con diti on.

D By givi ng a pulse.

3. A NAND gate con sists of D .

A an OR gate followed by an in verter

B an AND gate followed by an in verter

C an AN

D gate followed by an OR gate

D an in verter followed by an AND gate

4. Un der what con diti on is the output of a two-i nput XOR gate logic-high? B

A Its in puts are simulta neously at the same logic level.

B Its in puts are simulta neously at opposite logic levels.

C Its in puts are logic-low.

D its in puts are simulta neously logic-high.

2.2

Write T or F for each stateme nt

T 1. The CPU uses the in put and output un its to com muni cate with the outside world.

F2. Main memory is sometimes called exter nal memory.

F3. After execution the program and the related files of data and files of information will be retained in the main memory for later use.

F4. Personal computers have not the features of the larger system..

T5. Large systems offer higher process ing speeds for user and retur n more data tha n PCs.

F6. CPUs all size have primary storage, arithmetic logic, and the con trol sect ion.

F7. The output device is the heart of any computer system.

T8. The in put/output devices and auxiliary storage un its of a computer system are called peripherals.

F9. The in strume nt of in terpretati on and com muni cati on betwee n huma ns and computers system of all sizes is CPU.

an F10 Special purpose computers can adapted to many situation by giving them appropriate program.

F11 .A mi nicomputer is the smallest and least expe nsive type of computer.

T12. A special purpose computer performs only one specific task and thus lacks versatility.

T13. The larger the system the greater is its process ing speed, storage capacity.

T14. Mai nframe computers are desig ned to process complex scie ntific applicati on.

T 9. The main memory in a gen eral-purpose computer is made up of RAM in tegrated

circuit chip.\

F 10. When the power is turned on, the program coun ter is set the first address of the bootstrap loader

by the software of the computer.

T 11. The read-write heads con tact the surface of the floppy disks.

T 12. The data on a particular track will be switched automatically onto a spare track

by the computer before a catastrophic failure would occur.

F 14. The read write heads stay on the same track continuously when the disk drive is

Worki ng

F 16. The possible symbols in the binary nu mberi ng system are q to 9.

F 17. The decimal value of 16 is represented in 4 bits BCD as 00010101.

F 18. Alpha nu meric versions of BCD com monly use 6,7or 8 bits to represe nt characters.

F 19. A 6 bit alpha nu meric code can represe nt 128 differe nt characters.

F 22. Eight bit codes are limited to represe nting 128 differe nt characters.

T23. An extra check (or parity ) bit is often added to each 6, 7, or 8 bit character represented in storage so that it will be possible to detect codi ng errors that may occur.

T 24. If a computer uses an odd parity format to detect errors in character codes, the n every valid character code will always have an odd number of 1 bits.

T 25. Processor comes with a unique set of operati ons called an in struct ion set.

F 26. In an in struct ion, opera nds specify the fun cti on to be performed.

T 27. A processor's job is to retrieve in structio n from memory and perform step by

step operati ons,

3.3 True or False

F1 All operati ng systems on various computers take the same size.

F 2 All operati ng systems were writte n in a low level Ian guage.

T3 The user can't use the computers at all if there is no operating system on the computers.

F4 The operati ng system exists in the lowest layer of a computer.

T5 The system calls are provided by the operati ng system.

T 6 A computer's operati onal software defi nes the schedule of jobs await ing executi on.

F7 Though an operati ng system can schedule the executi on of jobs, it does not man age the availability of I/O devices.