计算机专业英语习题答案

+ 答案习题

Write T or F to each statement

T6. An asynchronous device is a clocked device.

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

T8. The repetition 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 input may occur at any time.

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

T13. A unidirectional shift register is capable of shifting in one direction only.

F14. In a shift-left register the serial input determines what goes into the leftmost position during the shift register.

F15. To provide parallel transfer capability some additional input and output lines should be provided to the shift register.

Choose the best answer for each of the following

1. How can the output of a logic gate be energized C

A By changing its inputs.

B By remaining its inputs unchanged.

C By meeting the specific input condition.

D By giving a pulse.

3. A NAND gate consists of D .

A an OR gate followed by an inverter

B an AND gate followed by an inverter

C an AN

D gate followed by an OR gate

D an inverter followed by an AND gate

4. Under what condition is the output of a two-input XOR gate logic-high B

A Its inputs are simultaneously at the same logic level.

B Its inputs are simultaneously at opposite logic levels.

C Its inputs are logic-low.

D its inputs are simultaneously logic-high.

Write T or F for each statement

T 1. The CPU uses the input and output units to communicate with the outside world.

F2. Main memory is sometimes called external 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 processing speeds for user and return more data than PCs.

F6. CPUs all size have primary storage, arithmetic logic, and the control section.

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

T8. The input/output devices and auxiliary storage units of a computer system are called peripherals. F9. The instrument of interpretation and communication between humans and computers system of all

sizes is CPU.

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

F11 .A minicomputer is the smallest and least expensive 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 processing speed, storage capacity.

T14. Mainframe computers are designed to process complex scientific application.

T9. The main memory in a general-purpose computer is made up of RAM integrated circuit chip.\

F10. When the power is turned on, the program counter is set the first address of the

bootstrap loader by the software of the computer.

T11. The read-write heads contact the surface of the floppy disks.

T12. The data on a particular track will be switched automatically onto a spare track by the computer before a catastrophic failure would occur.

F14. The read write heads stay on the same track continuously when the disk drive is Working F16. The possible symbols in the binary numbering system are q to 9.

F17. The decimal value of 16 is represented in 4 bits BCD as 00010101.

F characters. 18. Alphanumeric versions of BCD commonly use 6,7or 8 bits to represent

F19. A 6 bit alphanumeric code can represent 128 different characters.

F22. Eight bit codes are limited to representing 128 different 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 coding errors that may occur.

T24. If a computer uses an odd parity format to detect errors in character codes, then every valid character code will always have an odd number of 1 bits.

T25. Processor comes with a unique set of operations called an instruction set.

F26. In an instruction, operands specify the function to be performed.

T27. A processor's job is to retrieve instruction from memory and perform step by

step operations,

True or False

F1 All operating systems on various computers take the same size.

F 2 All operating systems were written in a low level language.

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

computers.

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

T5 The system calls are provided by the operating system.

T 6 A computer's operational software defines the schedule of jobs awaiting

execution.

F7 Though an operating system can schedule the execution of jobs, it does not