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

Introduction of computer and programming concept, Classify computer system ...

Classify computer system according to capacity. How they are different from computers according to the classification of technology. Provide comparative study also.

Explain the array types, Array types An array is a collection of object...

Array types An array is a collection of objects of a one data type. The individual objects are accessed by their position in the array. This way of accessing is known as indexi

C programming, a c program to find the volume of sphere

a c program to find the volume of sphere

What are the two steps that happen while i say delete p?, A: N delete p is ...

A: N delete p is a two-step procedure: it calls the destructor, and then releases the memory. The code developed for delete p is functionally similar to this (supposing p is of typ

Prob, Given an integer n and a permutation of numbers 1, 2 ... , n-1, n wri...

Given an integer n and a permutation of numbers 1, 2 ... , n-1, n write a program to print the permutation that lexicographically precedes the given input permutation. If the given

How does a structure differ from an array, Question : (a) What is a str...

Question : (a) What is a structure? Provide a simple example of your own to illustrate this feature. (b) How does a structure differ from an array? (c) Describe a structu

Described smart pointer?, A: A smart pointer is a C++ class which mimics a ...

A: A smart pointer is a C++ class which mimics a regular pointer in syntax and some semantics, however it does more. Since smart pointers to distinct types of objects tend to have

Lcm, lcm program.

lcm program.

Tool for checking memeory leak, what would be the best tool for debuggingg ...

what would be the best tool for debuggingg memory leaks in c/c++ programming

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