# hello.s
# This is our first program in the MIPS assembly language.
# Let's print out a string and number.
# To perform I/O, we need to make a system call.  This usually involves
# writing 3 instructions - 
#   first, select the type of I/O function by specifying a value for $v0
#     (list of possible codes is given in your book on page A-49)
#   second, initialize $a0 to the argument you want
#   third, use syscall instruction to do the I/O action
# Notes on instructions:
#   li = put a constant into a register
#   la = put the address of an array/string into a register
#   move = copy the value from one register into another
	
	.data			# Data segment has array/string declarations
msg:	.asciiz "Hello, world.\n"
msg2:	.asciiz "Goodbye.\n"
	
	.text			# Text segment has instructions.
main:				# You have to label the start of program.
	li $v0, 4		# print the message
	la $a0, msg
	syscall

	li $s1, 12		# Find the sum of 2 numbers.
	li $s2, 23
	add $s3, $s1, $s2

	li $v0, 1		# print an integer
	move $a0, $s3
	syscall

	li $v0, 10		# end of program
	syscall