Microcontrollers - Dec 2012

Electronics & Communication (Semester 4)

TOTAL MARKS: 100
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any four from the remaining questions.
(3) Assume data wherever required.
(4) Figures to the right indicate full marks. 1 (a) Mention the difference between RISC and CISC processor.(6 marks) 1 (b) Explain function of following pins of 8051:
i) EA
ii) ALE
iii) PSEN
iv) RST(6 marks) 1 (c) Explain the internal memory organization of 8051.(6 marks) 2 (a) With necessary examples, explain immediate, bit direct and indexed addressing mode of 8051.(6 marks) 2 (b) Explain the effect of following instructions:
i) MOVX A, @dptr
ii) DJNZ R3, next
iii) DA A
iv) LJMP label(8 marks)

Write a program segment to realize following:

2 (c) i) Exchange contents of external data memory 8100 h with contents of internal data memory 40 h.
ii) Exchange contents of A-register and B-register using stack(6 marks) 3 (a) What do you understand by assembler directives? Explain the following assembler directives:
i) ORG
ii) END
iii) EQU(8 marks) 3 (b) Write an ALP to convert a 2-digit BCD number to binary.(6 marks) 3 (c) Write a delay program to generate a delay of 10 ms. Assume a crystal of 11.0592 MHz. Show delay calculation clearly.(6 marks) 4 (a) Explain the usage of the port pins of 8051.(6 marks) 4 (b) With necessary interface diagram, write a C program to generate a triangular wave using DAC interface.(6 marks) 4 (c) With necessary interface diagram, write a program to display "VTU2012" on a LCD interface.(8 marks) 5 (a) Mention the difference counter mode and timer mode of operation. With necessary format, explain the various bits of TMOD-SFR.(6 marks) 5 (b) Write an 8051 C program to generate a square wave of 2 kHz using timer 1, mode 2. Show the calculations clearly. Assume a crystal frequency of 11.0592 MHz.(8 marks) 5 (c) Explain the interrupts of 8051 clearly mentioning the vector address and priorities.(6 marks) 6 (a) Explain the various modes of serial communication operations.(6 marks) 6 (b) Write a program to transmit a message "VTU" serially at a band rate of 9600. Take crystal frequency as 11.0592 MHz.(8 marks) 6 (c) Explain with a neat diagram, the functional block diagram of 8255.(6 marks) 7 (a) With necessary block diagram, explain the architecture of MSP 430.(8 marks) 7 (b) Explain clock system of MSP 430.(8 marks) 7 (c) Explain the use of registers PxDIR and PxOLT.(4 marks) 8 (a) Explain various low power operations modes of MSP 430.(10 marks) 8 (b) Explain the bits of TCON register. Write an 8051 C program to toggle only bit P1.5 continuously every 50 msec. Use timer 1 to generate the delay. Assume XTAL=11.0592 MHz.(10 marks)