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

Comp 100, I have an account in my www.itlab.com and i have a test and it s...

I have an account in my www.itlab.com and i have a test and it should do tonight, so do you have any one to help me and do this test and it is about excel

Star topology, Ask conceptual question answer about star topology#Minimum 1...

Ask conceptual question answer about star topology#Minimum 100 words accepted#

What is a view, Question (a) What is a view? (b) Can we use a view t...

Question (a) What is a view? (b) Can we use a view to insert or update a record into a table? Do we have any limitation to perform the above command? (c) The syntax to cr

Education and society, mention the aims of education in present scenario

mention the aims of education in present scenario

Project on ASP .NET MVC 5, I am looking for a project which is based on ASP...

I am looking for a project which is based on ASP.NET MVC 5.Could you please help me ?

C++, You are to code a C++ program that will read the file IntList into an ...

You are to code a C++ program that will read the file IntList into an integer array. There are no more than 20 integers in the file. After all of the data is read into the file,

Ipx for lan, explain ipx for lan and spx

explain ipx for lan and spx

Choice of medium - transmission channels, Choice of Medium: All the tr...

Choice of Medium: All the transmission channels discussed in the foregoing paragraphs can be used as point to point connections or as broadcast systems. Transmitting informati

What are the tasks of ALU and their subcomponents, ALU’s tasks and their s...

ALU’s tasks and their suitable subcomponents: Addition and subtraction these two tasks are carried out by constructs of logic gates, such as half adders and full adders. While they

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