Due Thursday, October 18
15 points
For this assignment write a MAL program that returns the sum of integers from 1 to n, where n is entered by the user. The program should continue to prompt for n and display the sum as long as the user enters a positive number. When the user enters 0 or a negative integer, the program should not print the sum. Instead, it should print a message indicating that the program is terminating.
You should read the web page Using SPIM and XSPIM before attempting this lab.
To begin with, create a file containing the code in sums.s using the UNIX editor of your choice. Take care to enter the code correctly. It is difficult to locate errors until you have acquired more experience.
The program in sums.s
just prompts the user for a single
integer n and displays the sum of integers from 1 to
n.
Run the program several times using xspim
.
See Assembling and Running MAL
Programs with XSPIM for instructions on the use of
xspim
.
When you are comfortable with xspim
, edit the
sums.s
file to add an outer loop that repeats the prompting,
getting n, and displaying the sum.
You may want to keep xspim
running, opening another
xterm
window to do editing.
Be sure to save changes before clearing, loading, and running in
xspim
.
Test the sums
program using the xspim
program,
entering various numbers until you are sure that it is running correctly.
Turn in a typescript showing the
contents of your final version of sums.s
and a
spim
session with the following user inputs:
For making typescript, you should run spim
rather than
xspim
.
See Assembling and Running MAL
Programs with SPIM for instructions on the use of spim
.