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

Assignment, Write a program that computes the cost of a long distance call....

Write a program that computes the cost of a long distance call. The cost of the call is determined according to the following rate schedules. a. A call made between 8:00 AM and

Area under curve, Write a program to find the area under the curve y = f(x)...

Write a program to find the area under the curve y = f(x) between x = a and x = b, integrate y = f(x) between the limits of a and b. The area under a curve between two points can b

Class & objects, how objects are initialized dynamically?

how objects are initialized dynamically?

Can a copy constructor admit an object of the similar class , Can a copy co...

Can a copy constructor admit an object of the similar class as parameter, rather than reference of the object?

Function that has two int parameters number , Write a function that has two...

Write a function that has two int parameters num and n, and returns TRUE when the nth bit in num is 1, otherwise FALSE. This function should use the function in the above problem.

Vogels approximation transportation problem, Vogels approximation transport...

Vogels approximation transportation problem in c language source code

C program, Write a ‘C’ program to accept any 3 digit integer number from th...

Write a ‘C’ program to accept any 3 digit integer number from the keyboard and display the word equivalent representation of the given number.

Board coloring, programing code on board coloring in clanguage

programing code on board coloring in clanguage

Structured design of programs, Within software engineering, software is ver...

Within software engineering, software is very rarely written by a single software engineer. Usually a team of engineers write a program; therefore a formal structural design approa

Procedure to add two numbers in a recursive manner, (a) Write a procedure c...

(a) Write a procedure called (add x y) that adds two numbers in a recursive manner. Specifically, note that x + y = (x + 1) + (y - 1) and x + 0 = x. (b) Using the substitution m

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