Redpine Signals Question-Paper Contributed by P.RADHA updated on Apr 2019

REDPINE PAPER ON 25th  AUGUST 2011  AT GNIS, HYDERABAD

Hi all
I have attended the REDPINE company .i.e one of domine company for ECE students.The cut off is 70%.
First there is a written test and then interview.

Written test consists of 4 secetions
Digital--30marks
Communications---20marks
Computer---20marks
Aptitude--30marks

Each questions carry weightage differently

Digital:
It includes both STLD ,VHDL and Microprocesers.
1)Design 3:1 multiplexer  using one tri-state buffer,AND gates and NOT gates.

2)The no of 2-input XOR gates required to design 19-inprt XOR gate?

3)A 26Kbyte memory,there is memory it contains 12 adderss lines and 4 bit data  bus,the number of these type of memories required to design 26Kbyte memory?

4)Write a VHDL or Verilog HDL code for
input:a,clock,reset
output:out
out is assigned to 1 when a is '1' for two clock cycles.

5)what is the output of following fig.100ps is the delay for XOR gate and 50ps for AND gate .all +ve and -ve edges start at boundaries of nanoseconds.(actually the output of fig is  A(B(notC)+(not B)C) ,and the waveforms are given).

6)design forwhich the output is 10MHz clock,input to that circuit is 30MHz.

Communications:
7)  What is shonan's theorem?

a)p(X<=infinte)=?
b)X is zreo mean and a unit variance random variable,them find the mean and variance of y
y=2X+5;
9)because of error 000 is coded insted of 0 ,111insted of 1.then what is the error correction and error detection capability of the system?
10)A deterministic signal whose pdf is given then we have to find the minimum sampling frequency needed ?

Computers:

11)one question on bit rate.....(i didn't rember exactly)
12)what is the application os MS world and Msperfect application is?
13)write a c code for factrial using recursion.
14)some statements are given like
putup::then lift the pen move accordingly without drawing aline,
FD N::move forward (N distance)
LD N:: move left at an angle of 90 degrees then move N
RD N::move right at an angle of 90 degrees then move  N
putdown::draw alin following instructions
what is the output of following code
putdown
FD 10
putup
LD 1
FD 2
putdown
RD 8
so on like is....

13)what is the output
int a[10]={0,1,2,3,4,5,6,7,8};
int *p=a;
printf("%d\n",*p++);

14)two genaral knowledge questions..
15)what is expansion of GMSK?
16)find out the 5 digit number in that 4th digit is 4 nore than the second digit ,3rd digit is  3 less the 2nd digit andfirst is 3 times the last digit?
some more questions are there in this section ,but they are somewhat easy .