Hardware and Software Design Interview Questions & Answers

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A Turing machine is a theoretical computing machine invented by Alan Turing (1937) to serve as an idealized model for mathematical calculation. A Turing machine consists of a line of cells known as a "tape" that can be moved back and forth, an active element known as the "head" that possesses a property known as "state" and that can change the property known as "color" of the active cell underneath it, and a set of instructions for how the head should modify the active cell and move the tape. At each step, the machine may modify the color of the active cell, change the state of the head, and then move the tape one unit to the left or right.

It searches through local DNS cache, if nothing is there, it queries the ISP?s DNS server.

Generally for integer memory is 2 bytes for character is 1 byte

char * and int * are pointers. they point to a memory location hence there size is the same, which is the size of the address space.

I am writing for Microcontrollers. ldi r16,$F0 ldi r17,$08 ldi r18,$00 ldi r19,$00 loop: rol r16 back: brcs one inc r19 dec r17 brne loop end:rjmp end one:inc r18 rjmp back

int count1s =0; while(num != 0){ if(num & 1 == 1){ count1s++; } num= num>>1; } printf("%d", count1s);

RISC-Means Reduced Instruction Set Computer.a Risc
system has reduced number of instructions and more
importantly it is load store architecture were pipelining can be implemented easily.Eg.ATMEL AVR.

CISC-Means Complex instruction set architecure.A CISC
system has complex instructions such as direct addition between data in two memory locations.Eg.8085.

because it has got seperate program and data memory(highly pipelined architecture)

A real time system is a computer system that updates the information at the same rate it receives it. It is of two types, hard real time system and a soft real time system.

Real-time operating systems are: QNX, LynxOS, OS-9, Intergrity, Katix, Fusion, IRIX, DeltaOS, eCos, AMX, CMX-RTX, INTime, PDOS and many others.

DOS is not a RTOS (real time Operating system), however MS DOS can be used with certain APIs to achieve the RTOS functionality. For example, the RT Kernel (Real Time Kernel) which can be used with MS DOs to achieve the RTOS functionality. Other example is of Tics. Tics is delivered as a hardware support file for MS DOS.

A shell is a program that presents an interface to various operating system functions and services. The shell is so called because it is an outer layer of interface between the user and the innards of the operating system (the kernel). Kernel is the one which manages all the resources of the Operating System.

Binary Search: Search a sorted array by repeatedly dividing the search interval in half. Begin with an interval covering the whole array. If the value of the search key is less than the item in the middle of the interval, narrow the interval to the lower half. Otherwise narrow it to the upper half. Repeatedly check until the value is found or the interval is empty.

Hashing provides a fast way to search a large, unsorted data set at the cost of extra memory. It is described as "directly referencing records in a table by doing arithmetic transformations on keys into table addresses."

#include #include int fact (int ); void main() { int n, a; cout<<"enter any value"; cin>>n; a=fact(n); cout<< a; getch(); } int fact (int x) { if((x==0) || (x==1)) return 1; else return(x*(x-1)); }

In C++

Constructor:This is a member of class which involkes when the object is created.Purpose of constructor is to intialise the objects with required values.

Destructor: It is a member of class which involkes when the object is out of scope.The purpose of destructor is to clear the heap memory.

waterfall model is the linear model. The process is done by step by step. We couldn't stop in between of the process. prototype model: after get the model by low cost budget only we are implementing that product. so, its efficient.

Testing is used for estimate the quality of the product. Unit Testing is tested for each part of the product. Integrate the unit and tested.