Write this ARM assemble language program, Basic Computer Science

Assignment Help:
Programming Assignment
CS252 Spring 2014

Write an ARM assembly language subroutine that performs according to the following specification (Caesar cypher).

Given a mixed case alphabetic string from the C driver program, convert it to all upper case and create a new string for return to the C program. The new string has the characters from the old string replaced by upper case characters from the alphabet offset by the given amount in the alphabet.

If the character string is ‘Abc’ with an offset of -3 the new string would be ‘XYZ’. For characters in the alphabet such as ‘mno’, the alphabet is ‘JKL’. The beginning of the alphabet is wrapped to the end.

To convert a character to upper case, AND the character with 0xDF. Do not process the space character (leave it as a space) or the NULL byte terminator but be sure to include the NULL byte in the new string.

The C driver code:
/* C code for cipher */
#include
#include

extern char * cypher( char * s, int offset ) ;

int main( int argc, char * argv[] )
{
?char string[] = "The quick brown fox jumped over the lazy dog" ;
?char * result ;
?int offset = -5 ;

?result = cypher( string, offset ) ;
?printf( "Original:%s\n", string ) ;
?printf( "Coded: %s\n", result ) ;
?
?exit( 0 ) ;
}

The assembly routines definition is:
?extern char * cypher( char * s, int offset )
?where?char * s is the pointer to the string,
?int offset is the integer distance to move
?returns a pointer to a string.

To determine the length of the string in order to reserve space for the new string use the library routine strlen. Register a1 contains a pointer to the string to measure and on return register a1 has the number of characters in the string. You need to add one to this result since strlen does not account for the null byte at the end.
You can pass this length to the malloc library routine to obtain space for the new string.

Related Discussions:- Write this ARM assemble language program

Instructions for cycles: loop, They transfer the process flow, provisionall...

They transfer the process flow, provisionally or totally, to a destiny, replicating this action until the counter is zero. LOOP LOOPE LOOPNE LOOP INSTRUCTION reason: To produce a c

Mr, Please what is the different between computer science and information t...

Please what is the different between computer science and information technology? Which of this require too much reading? Thanks

Explain process creation and process termination, Question 1 Explain diffe...

Question 1 Explain different functions of an operating system. Explain the evolution of operating systems Question 2 Explain process creation and process termination Ques

What is multi-protocol label switching (mpls), QUESTION (a) What is Mul...

QUESTION (a) What is Multi-Protocol Label Switching (MPLS)? List the main advantage of running MPLS in a service provider network (b) What is a label? Explain the structure

Multithreaded Programming in python, Running more than a few threads is lik...

Running more than a few threads is like running several different programs at the same time as, but with the following profits: • Multiple threads inside a process share the same d

Introduction to FCB , There are two kinds of FCB, the normal, whose length...

There are two kinds of FCB, the normal, whose length is 37 bytes and the expanded one of 44 bytes. The FCB is created of data given by the programmer and by data which it takes dir

Construct a conditional profits table, Question (a) A dairy wants to de...

Question (a) A dairy wants to determine the quantity of butter it should produce to meet the demand. Past records have shown the following demand pattern:

Programming Project 1, Programming Project You will implement 2 algorithms...

Programming Project You will implement 2 algorithms to solve the single source shortest paths problem, Bellman-Ford Algorithm and Dijkstra''s algorithm Allowed programming languag

Internal structure of agents - artificial intelligence, I n t e rnal St...

I n t e rnal Structure of Agents We have looked at agents in terms of their external influences and behaviors: they take input from the environment and perform rational act

Opening documents situated on different computers - network, Opening Docume...

Opening Documents Situated on Different Computers In order to work with documents situated on other computers, you need sufficient rights to access the folder in which it is

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