# xSpim Demo Program
# 
#   CPE 315
#   fall 2001
#
# By: Dan Stearns
# Date:  
# Modifications:
#           
#
# Notes:
#        The constants in the address loading sequence (lui/ori)
#        are entered from the global symbol table because...
#        this assembler lacks assembly-time arithmetic operations
#
#

# declare global so programmer can see actual addresses.
.globl welcome
.globl prompt
.globl sumText

#  Data Area
.data

welcome:
.asciiz " This program adds two numbers \n\n"

prompt:
.asciiz " Enter an integer: "

sumText: 
.asciiz " \n Sum = "

#Text Area (i.e. instructions)
.text

main:

# Display the welcome message;  lui and ori constants are obtained
#  manually from the global symbol table.  One will surely appreciate
#  the la pseudoinstruction after this exercise.
ori     $v0, $0, 4			
lui     $a0, 0x1001
ori     $a0, $a0,0
syscall

# Clear $t0 for the sum
ori     $t0, $0, 0	

# Display prompt
ori     $v0, $0, 4			
lui     $a0, 0x1001
ori     $a0, $a0,0x22
syscall

# Read 1st integer and add to sum
ori     $v0, $0, 5
syscall
addu    $t0, $v0, $t0

# Display prompt
ori     $v0, $0, 4			
lui     $a0, 0x1001
ori     $a0, $a0,0x22
syscall

# Read 2nd integer and add to sum
ori	$v0, $0, 5			
syscall
addu    $t0, $v0, $t0 

# Display the sum text
ori     $v0, $0, 4			
lui     $a0, 0x1001
ori     $a0, $a0,0x36
syscall

# Display the sum
ori     $v0, $0, 1			
add 	$a0, $t0, $0	 
syscall

# Exit
ori     $v0, $0, 10
syscall