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

Structures, A more advanced data type is the structure; here we can define ...

A more advanced data type is the structure; here we can define a template as a collection of different variables e.g.     struct birthdate   {     int month;     int day;

Write a program to illustrate passing structure to function, Write a Progra...

Write a Program to illustrate passing structure to function? # include struct customer { int id; char name[15]; }; void func_struct(struct customer); main() { struct c

Memory allocation for objects, when a class is defined the compiler will no...

when a class is defined the compiler will not allocate memory. This is true only for data member not for member function.  As soon as the member function is defined  the require

Convert coordinate - c++ program, Convert coordinate: class rect{  ...

Convert coordinate: class rect{                 private :                 float  x,y;                   public :                 void  input()

Last ant on rod, There are ''''n'''' ants on a ''''n+1'''' length rod. The ...

There are ''''n'''' ants on a ''''n+1'''' length rod. The ants are numbered from 1 to n and are initially placed at positions starting from position 1 till position n. They are mov

C program to create, Aim: To implement a program to create, update & displ...

Aim: To implement a program to create, update & display account & admin record of person using display account & admin records of person using virtual base class.. Code:

System programing, #quesdifferentiate betweenrelocatable and self relocatin...

#quesdifferentiate betweenrelocatable and self relocating program with exampletion..

What is precedence and order of evaluation, Precedence and Order of evaluat...

Precedence and Order of evaluation The languages follow a standard precedence for basic operators. Precedence rules help in deleting ambiguity of the order of operations perfor

Mr. D. Mclean, A Network of routers have been configured for the ...

A Network of routers have been configured for the purposes of handling data traffic within your company. You would like to have an application that does a network

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