Program to calls to echo the typed characters, C/C++ Programming

Assignment Help:

Write a main program that uses these system calls to echo the typed characters. The pseudo code will look something like:

void traphandler ()  {

   if (R0 == 0) { // read system call

      R1 = getchar(); // poll the status register of the IO terminal until a char is available then load it into R1

   } else if (R0 == 1) { // write system call

      putchar(R1); // just store R1 to memory location 0xfff0

   }

   enableInterrupts();

}

void main() {

   char c;

   while (1) {

      c = read();  // set R0 to 0 can issue the 'trap' instruction, result will be in R1

      write(c);  // set R0 to 1 and set R1 to 'c' and issue the 'trap' instruction

   }

}


Related Discussions:- Program to calls to echo the typed characters

Ascii string related, A string S is said to be "Super ASCII", if it contain...

A string S is said to be "Super ASCII", if it contains the character frequency equal to their ascii values. String will contain only lower case alphabets (''a''-''z'') and the asci

Describe how a structure differs from a union, Question : (a) How does...

Question : (a) How does a structure differ from an array? (b) Describe how a structure differs from a union? (c) Declare a union called ‘clothes' which consists of the

Determine the canonical form, Rule: To determine the canonical form we s...

Rule: To determine the canonical form we should OR the min terms. A min term is defined as a Boolean equation of the input if the output is logic '1'. If the input is logic '1'

FlipFlaps fltk project, The project is to design and write a C++11/FLTKgame...

The project is to design and write a C++11/FLTKgame program with a graphical user interface.The game is based on "pancake sorting," as described at http://en.wikipedia.org/wiki/P

Add the two complex no.s given by user - c++ program, THIS PROGRAM IS TO AD...

THIS PROGRAM IS TO ADD THE TWO COMPLEX NO.S GIVEN BY THE USER  */ #include #include #include struct complex     {     int real;     int imag;     }; void main()  {  clrs

How the operations are performed in a single linked list, Question: (a)...

Question: (a) Explain a linked list. (b) Describe the three different types of linked list with the help of diagrams. (c) Give two advantages and two disadvantages

How to use turbo c, Sir i want to know all the basic knowledge of turbo c.

Sir i want to know all the basic knowledge of turbo c.

What is a command line argument and what is its use, Question 1) What are ...

Question 1) What are the commonly used input/output functions in C? Question 2) What is the difference between function declaration and function definition? Write a recursive

Operators and their expression in cpp, Operators in C++: All C operator...

Operators in C++: All C operators are valid operators in C++ also.  Besides C++ has developed some new operators like Operators and their Expression: 1.      Logical op

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd