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

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

   }

}

Posted Date: 3/8/2013 6:26:43 AM | Location : United States







Related Discussions:- Program to calls to echo the typed characters, Assignment Help, Ask Question on Program to calls to echo the typed characters, Get Answer, Expert's Help, Program to calls to echo the typed characters Discussions

Write discussion on Program to calls to echo the typed characters
Your posts are moderated
Related Questions

c program to construct a structure: struct sensus                 {                                 char name[30];                                 long int population;

Write a program that takes 3 small letters as input and sort them according to their ASCII value.

Money is immutable and is associated with a currency. When two money entities are added or subtracted be sure to consider currency conversion. You must create a money object result

how to make a program this struct items/product

#decode the code

Primarily the term alignment refers the tendency of an address pointer value to be a multiple of some power of two. Thus a pointer with two byte alignment contains a zero in the le

For this program you will add and test 2 new member functions to the IntSLList class posted on the website. The two member functions are: insertByPosn(int el, int pos) Assuming t

P o i n t e r d e c l a r a t i o n f o r me m b e r f un c t i o n : M e t h o d 1 : W h e n C l a ss i s n o t

C Program to FIND VOWELS   void main() {           char str[50];           int ac=0, ec=0, ic=0, oc=0, uc=0;           int i,stln,vc,word=1;           clrscr