CLASS: M.Sc. PHYSICS 12A/ 405
St. JOSEPH’S COLLEGE (AUTONOMOUS) TIRUCHIRAPPALLI – 620 002
TIME: 3 Hrs.
SEMESTER EXAMINATIONS – APRIL 2012
MAXIMUM MARKS: 100
SEM SET PAPER CODE TITLE OF THE PAPER
II 2011 10PPH2107 MICROPROCESSOR AND MICROCONTROLLER
Answer all the questions:
SECTION – A
20 x 1 = 20
Choose the correct answer:
1. In 8085, the address bus is a group of _______ lines a) 8 b) 16 c) 32 d) 64
2. _______ is a 16 bit register which deals with sequencing the execution of instructions a) Accumulator c) Program counter b) d)
Stack pointer
Flag
3. The execution of the _______ instruction uses the contents of the accumulator to perform enable or disable mask set control function. a) ROM c) RAM b) SIM d) RIM
4. The timer / counter mode (0) register of microcontroller 8051 operates _______ bit address. a) 8 b) 13 c) 32 d) 64
5. In 8255, a control word with bit D
7
= 0 is called _______ mode. a) Hand shake I/O c) BSR b) d)
Strobed I/O
Bidirectional I/O

Fill in the blanks:
6. The special signal ‘ALE’ in 8085 refers to _______.
7. The beginning of the stack is defined in the program by using the instruction _______.
8. The 8051 has _______ bytes of internal RAM address register.
9. The serial port of microcontroller 8051 can operate in _______ different modes.
10. The LCD display module has _______ pins.
State True or False:
11. The 8085 has five interrupt signals that can be used to interrupt a program execution.
12. In 8085, a subroutine cannot be called unconditionally.
13. The SFR bank register address has the range of 80H to FFH.
14. In 8051, the IP and IE special function registers are not used for executing interrupts.
15. For 4

4 matrix keyboard interfacing, port 1 and port 3 of 8051 are used.
Answer in one or two sentences:
16. Define instruction cycle.
17. What is a subroutine?
18. What is the purpose of PSW register?
19. Mention the various types of interrupt signals.
20. What are peripheral devices?
SECTION – B
Answer all the questions: 5 x 6 = 30
21. a. Draw and explain the timing diagram of STA instruction. b.
OR
Describe the I/O interfacing using memory mapped I/O.
22. a. Write an assembly language program to find 2’s complement of an 8 bit number.
OR b. Write an assembly language program for shifting of a 16- bit number left by 2-bits.
23. a. Distinguish between the microprocessor and microcontroller.
OR

b. Draw and explain the structure of internal RAM.
24. a. Draw the interfacing diagram of RS232 with 8051 and explain its operation.
OR b. How of 8051. are interrupts handled? Explain external
25. a. Draw and explain the programmable peripheral interface of Intel 8255.
OR b. Explain the microprocessor based traffic controller.
SECTION – C
Answer any FOUR questions:
26. Draw and explain the architecture of microprocessor 8085.
4 x 12.5 = 50 interrupts
27. Write an assembly language program to find the largest and smallest number in a data array.
28. Draw and explain the pin description of 8051 and also give the applications of microcontroller.
29. Explain the different modes of serial communication programming and mention their baud rates.
30. Draw the interfacing diagram of stepper motor with 8051 and explain its operation.
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