# Program to read numbers until a zero, printing each in hexadecimal
ret:	.word	0	# space for return address
s:	.space 8
	.asciiz	\n
tr:	.asciiz	0123456789ABCDEF
main:	sw	$ra,ret		# save return address
ml1:
	syscall 5		# read number
	beqz	$v0,exit	# if number is 0, exit
	add	$a0,$v0,$0		# copy number to arg register
	bal	itohex		# convert to hex in s[]
	add	$a0,$0,s	# prepare to print s[]
	syscall	4		# print the string
	b	ml1		# repeat

exit:	add	$v0,$0,$0	# zero exit status
	lw	$ra,ret		# restore return address
	syscall	10		# return from main

itohex:	add	$t2,$0,s		# $t2 = &s[0] (used as end test)
	add	$t0,$t2,7	# $t0 = &s[7] (k)
loop:	and	$t1,$a0,0xF	# $t1 = I & 0xF
	lb	$t1,tr($t1)	# $t1 = tr[I&0xF]
	sb	$t1,0($t0)	# s[k] = $t1
	sla	$a0,$a0,-4	# I = I >> 4
	add	$t0,$t0,-1	# k--
	sub	$a1,$t0,$t2	# -->loop if k>=0
	bgez	$a1,loop	# -->loop if k>=0
	b 	$ra		# return
	.end	main