Psudo code for interrupt handler , C/C++ Programming

Assignment Help:

The rPeANUt simulator provides buffering of the characters that are typed into the terminal. However, this would generally not be the case so if the program did not consume a character before the next one is typed then a character may be lost. So in this next part of the lab you are required to write an interrupt handler for the IO terminal that will capture characters as they are typed and place them in a buffer. The read system call would then read them out of this buffer rather than directly from the device. The psudo code for interrupt handler with a single character buffer:

void iohandler () {

   if (buffcount == 0) {

      buff = getchar();  // no need to poll on the status register

      buffcount = 1;

   } else {

      getchar(); // no room in the buffer so we lost a character!!!

   }

   enableInterrupts();

}

void traphandler ()  {

   enableInterruptes();

   if (R0 == 0) { // read system call

      while (buffcount == 0) ;

      R1 = buff;

      buffcount = 0;

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

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

   }

}

char buff;

int buffcount;

void main() {

   buffcount = 0;

   enableIOterminalInterrupts();  // involves writing to the control register of the IO terminal device.

   char c;

   while (1) {

      c = read();

      write(c);

   }

}

 


Related Discussions:- Psudo code for interrupt handler

Functions, differentiate between inbuilt and user defined functions

differentiate between inbuilt and user defined functions

Described the scope resolution operator?, A: It allows a program to referen...

A: It allows a program to reference an identifier in global scope which has been hidden by another identifier along with the same name in the local scope.

Bank account system, To implement a back account system for new users

To implement a back account system for new users

Scope resolution operator, what are the significances of scope resolution o...

what are the significances of scope resolution operator? Illustrate with example

Change to palindrome, A palindrome is a string that reads the same from bot...

A palindrome is a string that reads the same from both the ends. Given a string S convert it to a palindrome by doing character replacement. Your task is to convert S to palindrome

Described inline function?, A: The inline keyword tells the compiler to sub...

A: The inline keyword tells the compiler to substitute the code in the function de_nition for each instance of a function call. Though, substitution takes place only at the compile

C++ program, Receive 3 numbers and display them in ascending order from sma...

Receive 3 numbers and display them in ascending order from smallest to largest ed#

Time table, programme for time table in c++

programme for time table in c++

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

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

Program, Define a class polynomial with three private data members a, b and...

Define a class polynomial with three private data members a, b and c of type double to represent the coefficient of two degree polynomial(ax^2+bx+c). Include a constructor in a pol

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