Rajiv Gandhi Proudyogiki Vishwavidyalaya 2006 B.E Electronics & Tele-Communication Engineering - Question Paper

June 2006
1. explain with cause :
(a) some ROM is always placed at the top of memory space in 8086 based microprocessor system.
(b) Buffers and latches are needed in microcomputer system
(c) Number of PUSH and POP kind instruction should be equal in a subroutine .
(d) RET kind instruction is executed at the end of a subroutine.

2. (a) discuss the different register of 8086 microprocessor. Draw the timing diagram for its operation in minimum mode (read operation.
(b) how will you set and reset the ‘Direction flag bit’ of flag register?

3. (a) how will you generate square wave of 50 Hz using PPI 8255?
(b) how will you inter face a DAC to microprocessor 8086 using any latching device? Draw the circuit diagram also.

4. Explain the operation of timer 8353 in various modes with the help of timing diagram. Write down the program in assembly language for 8086 to initialize this device. What is ‘Flying’ mode?

5. (a) How will you interface stepper motor using 8155 or 8255 ? How can you control the speed?
(b) How can you directly interface LED's to microprocessor without using any programmable peripheral device?

6. Explain the subsequent :
(a) RS232C
(b) MODEM

7. Describe the subsequent SFR of 8051 microcontroller :
(a) TMOD
(b) TCON
(c) SCON
(d) DPTR

8. Write short notes on any 3 of the subsequent :
(1) DMA controller
(2) Memory interfacing
(3) Call and JMP instruction of 8051
(4) Risc And Cisc processors – introduction
(5) LDT and GDT of 80286

Earning:   Approval pending.