AMIETE – ET/CS/IT (NEW SCHEME) – Code:
AE66/AC66/AT66
Subject: MICROPROCESSORS & MICROCONTROLLERS
Time: 3 Hours
Max. Marks: 100
NOTE: There are 9 Questions in all.
· Question 1 is compulsory and
carries 20 marks. Answer to Q.1 must be written in the space provided for it in
the answer book supplied and nowhere else.
· Out of the remaining EIGHT
Questions, answer any FIVE Questions. Each question carries 16 marks.
· Any required data not
explicitly given, may be suitably assumed and stated.
Q.1 Choose
the correct or the best alternative in the following: (2
10)
a. Find the 2’s complement of 
(A) 1001 (B) 1101
(C) 0001 (D) 1111
b. The pin of 8085 which de-multiplexes the address and
data pins is called
(A) HOLD (B) ALE
(C) HLDA (D) IO/M*
c. Maximum
executing time is required for the instruction
(A) MOV A, M (B) JMP adder
(C) CALL adder (D) NOP
d. After executing
the following instructions, the content of A register will be
LXI H, FFFFh
XR
A, A
MOV
A, L
ROR
(A) FEh (B) FFh
(C) EFh (D) OO
e. Which one of
the following interrupt is both level & edge controlled?
(A)TRAP (B) RST7.5
(C) RST 5.5 (D) RST 6.5
f. For serial input operating the following
instruction is used.
(A) RIM (B) SIM
(C) INTR (D) SID
g. In a programmable interrupt controller, the maximum number of
interrupting devices, that can be connected to the processor is
(A) 8 (B) 16
(C) 32 (D) 64
h. A
microcontroller differs from a microprocessor in the following feature.
(A) Internal memory (B) Two ground
(C) TWO Vcc s (D) DMA registers
i. An USART is used for
(A) Parallel communication (B) Serial communication.
(C)
DMA operation (D) Time function
j. The following are
bit-addressable SFRs in 8051 microcontroller :-
(A) P0 to P3, RB0-RB3,
PSW, TCON
(B) RB0-RB3, DPL, TL0, SBUF
(C)
P0 to P3, PSW, TCON, IE
(D) RB0-RB3, SP, PCON, TMOD
Answer any FIVE Questions out
of EIGHT Questions.
Each question carries 16
marks.
Q.2 a. Draw the architecture of 8085. Explain
various components. (8)
b. Give
comparison of different machines cycles.
(4)
c. Using NAND
gates or any other circuit, generate chip select signals for a 8K EPROM &
8K RAM to be interfaced to 8085. (4)
Q.3 a. Explain NOP and stack group of instructions.
(6)
b. Give the timing diagram for the instruction LXI, H adder
indicating all control signals. (4)
c.
Give any two examples for each of following:-
(i)
Data transfer instruction.
(ii) Arithmetic
instruction.
(iii) Logical instruction.
(6)
Q.4 a. Write an Assembly language program (ALP) to
multiply two 8 bit binary numbers. The result should be stored in two
registers. Provide suitable comments. (8)
b. Convert the
BCD number stored in memory to binary number and stored same in consecutive
memory location. (8)
Q.5 a. Explain the interrupt process of 8085 and
give sequence of steps in interrupt service routine. (8)
b. Explain EI and
DI instructions. (4)
c.
Mention various components of programmable peripheral interface and
explain various operational modes. (4)
Q.6 a. Write
an assembly program to simulate 4-bit ALU. (5)
b. Write an ALP to interface a 7 segment LED
display to 8085. Indicate the set up details and give the block diagram. (5)
c.
Explain 8279 key board and display controller. (6)
Q.7 a. Explain synchronous and asynchronous data
transmission. Using USART enumerating all steps involved in transmission and
reception of data. (8)
b. Generate a
square wave using 8253 Mode-3 oparation. (4)
c.
Mention various modes used in 8253 timer. (4)
Q.8 a. Explain
the concept and need for DMA. Give the format of control register and status
register of 8257. (8)
b. Write an ALP
to interface six interrupting device through 8259 to 8085. Give the sequence of
operations. (8)
Q.9 a. Draw
and explain the functional pin diagram of 8051 microcontroller. (8)
b. Write short
note on the following: (8)
(i) Program memory structure of 8051
microcontroller.
(ii) Data memory structure of 8051 microcontroller.