Computer Organization...
Tuesday, November 29, 2005
  UNIT 1,2,3
1. Find the corresponding decimal number for the binary number 101101

1*25+0*24+1*23+1*22+0*21+1*20 = 45
(101101) 2 = (45) 10

2. Find the corresponding binary number for the decimal number 41.6875

(41.6875) 10 = (101001.1011) 2

3. Find the equivalent decimal number of hexadecimal number F3
(F3) 16 = F*16 + 3
= 15*16 +3
= (243) 10

4. Add two numbers using 2’s complement
(-2)+4
1110 (2’s complement of -2)
0100

0010 è 2


5. Find 9’s complement for 546700
999999
546700
453299

6. Write the 10’s complement of the decimal number 2389
10’s complement of the decimal number 2389= (9’s complement of 2389) + 1=>7611

7. Draw the graphic symbol and truth table for AND, NOR gates.









8. What is minterms?
Each combination of the variables in a truth table is called a minterms.


9. Simplify the following expression using Karnaugh map
F (A, B, C) = å (3, 4, 6, 7)








10. What is don’t care condition?
Minterm, which may produce either 0 or 1, is termed as don’t care condition. This is useful to get more simplify expression. The symbol for don’t care condition is X.

11. Obtain the simplified expression of the following function using don’t care condition.
f (A, B, C ) = å (0, 2, 6)
d (A, B, C ) = å (1, 3, 5)









12. What is combinational circuit?
Combinational circuit is a connected arrangement of logic gates with a set of inputs and outputs.

13. Short notes on SR Flip-Flop.
SR Flip-Flop has three inputs. S (for set), R (for reset), C (for clock). Only when the clock signal changes from 0 to 1 can the output be affected according to the values in inputs S and R.







14. What are the classifications of integrated circuits depends upon the number of pins?
i. Small scale integration (SSI)
ii. Medium scale integration (MSI)
iii. Long scale integration (LSI)
iv. Very long scale integration (VLSI)

15. Convert the following octal number to decimal number
736.4

(736.4) 8= 7 * 82 + 3 * 81 +6 * 80 + 4 * 8-1
= 7 * 64 + 3 *8 + 6 *1 + 4/8 = (478.5) 10


16. What is Digital Computer? Draw the block diagram of digital computer.
Digital computer is a digital system that performs various computational tasks. They use the binary system, which has two digits: 0 and 1. A binary digit is called a bit.

Block diagram.









17. What is sequential Circuit? Draw the block diagram for it.
A sequential circuit is an interconnection of flip-flops and gates (combinational circuit).







18. What are the different logic families of integrated circuits?
TTL- Transistor- Transistor logic
ECL-Emitter-coupled logic
MOS-Metal-oxide semiconductor
CMOS-Complementary metal-oxide semiconductor

19. What is decoder?
A decoder is a combinational circuit that converts binary information from n-order
inputs to maximum of 2n unique outputs.

20. What is shift register?
A register capable of shifting its binary information in one or both directions is called shift register.

21. What are the two major types of memories used in computer systems?
Random Access Memory (RAM)
Read Only Memory (ROM)

22. What is Encoder?
An encoder is a digital circuit that performs the inverse operation of a decoder. An
encoder has 2n input lines and n output lines.
23. What is multiplexers?
A multiplexer is a combinational circuit that receives binary information from one of 2n input data lines and directs it to a single output line.


24. What is unidirectional shift register and bidirectional shift register?
A register capable of shifting in one direction only is called unidirectional shift register.
A register can shift in both directions is called a bidirectional shift register.

25. What is counter?
A register that goes through a predetermined sequence of states upon the application of input pulses is called a counter.

26. What is binary counter?
A counter that follows the binary number sequence is called a binary counter. n-bit binary counter is a register of n flip-flops.

27. What is memory unit?
Memory unit is a collection of storage cells together with associated circuits needed to transfer information in and out of storage.

28. What is word?
A memory stores binary information in groups of bits called word. A group of eight bits is called bytes.

29. What are the steps that must be taken for the purpose of transferring a new word to be stored into Random Access Memory?
i. Apply the binary address of the desired word into the address lines.
ii. Apply the data bits that must be stored in memory into the data input lines.
iii. Activate the write input.

30. What are the steps that must be taken for the purpose of transferring a stored word out of Random Access Memory?
i. Apply the binary address of the desired word into the address lines.
ii. Activate the read input.

31. Write some types of ROM.
Programmable read only memory (PROM)
Erasable Programmable read only memory (EPROM)
Electrical Erasable Programmable read only memory (EEPROM)

32. What is a micro operation?
The operations executed on data stored in registers are called micro operations.

33. Write some examples for micro operations.
Shift, count, clear and load

34. What is register transfer language?
The symbolic notation used to describe the micro operations transfers among registers is called a register transfer language.

35. What is register transfer?
Information transfer from one register to another is designated in symbolic, form by means of a replacement operator. The statement
R2ß R1
denotes a transfer of the content of register R1 into R2.

36. Short notes on memory transfer.
The transfer of information from a memory word to the outside environment is called a read operation. The transfer of new information to be stored into the memory is called a write operation. A memory word is symbolized by the letter M. The particular memory word among the many available is selected by the memory address during the transfer.

37. What are the classifications of micro operations in a digital system?
i. Register transfer micro operations transfer binary information from one register to another.
ii. Arithmetic micro operations perform arithmetic operations on numeric data stored in registers.
iii. Logic micro operations perform bit manipulation operations on non-numeric data stored in registers.
iv. Shift micro operations perform shift operations on data stored in registers.

38. What is binary adder?
The digital circuit that generates the arithmetic sum of two binary numbers of any length is called a binary adder.

39. Name some logic micro operations.
FßAÚB
FßAÙB
FßA

40. What is instruction code?
An instruction code is a group of bits that instruct the computer to perform a specific operation.

41. What is operation code?
The most basic part of an instruction code is its operation part. The operation code of an instruction is a group of bits that define such operations as add, subtract, multiply, shift and complement.

42. Write the difference between direct address and indirect address.
When the instruction specifies the address of an operand, the instruction is said to have a direct address. The instruction specifies the address of a memory word in which the address of the operand is found. It is called the indirect address.

43. What are the three types of instruction code formats?
Memory-reference instruction
Register reference Instruction
Input- output instruction.

44. What are the two major types of control organization?
Hardwired control
Micro programmed control.

45. What are the phases involving in instruction cycle?
Fetch the instruction from memory
Decode the instruction
Read the effective address from memory if the instruction has an indirect address.
Execute the instruction.

46. What is program?
A program is a list of instructions or statements for directing the computer to perform a required data processing task.

47. What is assembler?
Each symbolic instruction can be translated into one binary coded instruction. This translation is done by a specific program called an assembler. Because an assembler translates the symbols, this type of symbolic program is referred to as an assembly language.

48. Short notes on assembly language.
Each line of an assembly language program is arranged in three columns called fields. The fields specify the following information.
i. The label field may be empty or it may specify a symbolic address.
ii.The instruction field specifies a machine instruction or a pseudo instruction.
iii.The comment field may be empty or it may include a comment.

49. What is pseudo instruction?
A pseudo instruction is not a machine instruction but rather an instruction to the assembler giving information about some phases of the translation . Some examples for pseudo instruction symbols are.
ORG N
END
DEC N
HEX N

50. Short notes on two-pass assembler.
The input is scanned by the assembler twice to produce the equivalent binary program. A two-pass assembler scans the entire symbolic program twice. During the first pass, it generates a table that correlates all user-defined address symbols with their binary equivalent value. The binary translation is done during the second pass.

51. What is location counter?
To keep track of the location of instructions, the assembler uses a memory word called a location counter. (Abbreviated LC).


52. What is program loop?
A program loop is a sequence of instructions that are executed many times, each time with a different set of data. Program loops are specified in FORTRAN by a DO Statement.

53. What is compiler?
A system program that translates a program written in a high-level programming language is called a compiler.

54. What is index register?
When processor registers are used as pointers and counter, they are called index register.
 
Comments: Post a Comment



<< Home

ARCHIVES
September 2005 / October 2005 / November 2005 /

Click the sponsor links here to improve credit of this site



Powered by Blogger