DTEK

DTEK.asm

  # hexmain.asm
  # Written 2015-09-04 by F Lundevall
  # Copyright abandonded - this file is in the public domain.
# Q1: Print 0, since it cleans out the bits left of the fourth bit
# Q2: For numbers <9
	.text
main:
	li	$a0,0x0F		# change this to test different values

	jal	hexasc		# call hexasc
	nop			# delay slot filler (just in case)	

	move	$a0,$v0		# copy return value to argument register

	li	$v0,11		# syscall with v0 = 11 will print out
	syscall			# one byte from a0 to the Run I/O window
	
stop:	j	stop		# stop after one run
	nop			# delay slot filler (just in case)

hexasc:
	# Remove all bits but the 4 LSB saved to t0 from a0, ignore checking for negative number
	sll $t0, $a0, 28
	srl $t0, $t0, 28
	li $t1, 0x09
	ble $t0, $t1, number 
	
letter:
	# Remove so we get back to 0-9 range
	addi $t0, $t0, -0x0A
	# Add on 0x41 to start at 'A'
	addi $t0, $t0, 0x41
	j finish 
number:
	# Add on 0x30 to start at '0'
	addi $t0, $t0, 0x30
	j finish
finish:
	li $v0, 0
	add $v0, $0, $t0
	jr $ra
	
	
	  # timetemplate.asm
  # Written 2015 by F Lundevall
  # Copyright abandonded - this file is in the public domain.

#ASS3 Q:
# 1. We save all args, ra, gp, sp and fp because we have to (ra, sp and fp are important to restore our place in the stack and where we return to)
#  We save the t registers we use because we need them later on
#  We save the s registers because we're forced to by convention
# 2. None.
# 3. 133,162-166

.macro	PUSH (%reg)
	addi	$sp,$sp,-4
	sw	%reg,0($sp)
.end_macro

.macro	POP (%reg)
	lw	%reg,0($sp)
	addi	$sp,$sp,4
.end_macro
.macro PUSHALL()
	PUSH $a1
	PUSH $ra
	PUSH $t1
	PUSH $t2
	PUSH $t3
	PUSH $t4
	PUSH $a0
	PUSH $gp
	PUSH $sp
	PUSH $fp
	#$s0 - $s7
	PUSH $s0
	PUSH $s1
	PUSH $s2
	PUSH $s3
	PUSH $s4
	PUSH $s5
	PUSH $s6
	PUSH $s7
.end_macro
.macro POPALL()
	POP $s7
	POP $s6
	POP $s5
	POP $s4
	POP $s3
	POP $s2
	POP $s1
	POP $s0
	POP $fp
	POP $sp
	POP $gp
	POP $a0
	POP $t4
	POP $t3
	POP $t2
	POP $t1
	POP $ra
	POP $a1
.end_macro

	.data
	.align 2
mytime:	.word 0x5957
colonASCII: .byte 0x3A
timstr:	.ascii "text more text lots of text\0"
	.text
main:
	# print timstr
	la	$a0,timstr
	li	$v0,4
	syscall
	nop
	# wait a little
	li	$a0,2
	jal	delay
	nop
	# call tick
	la	$a0,mytime
	jal	tick
	nop
	# call your function time2string
	la	$a0,timstr
	la	$t0,mytime
	lw	$a1,0($t0)
	jal	time2string
	nop
	# print a newline
	li	$a0,10
	li	$v0,11
	syscall
	nop
	# go back and do it all again
	j	main
	nop
# tick: update time pointed to by $a0
tick:	lw	$t0,0($a0)	# get time
	addiu	$t0,$t0,1	# increase
	andi	$t1,$t0,0xf	# check lowest digit
	sltiu	$t2,$t1,0xa	# if digit < a, okay
	bnez	$t2,tiend
	nop
	addiu	$t0,$t0,0x6	# adjust lowest digit
	andi	$t1,$t0,0xf0	# check next digit
	sltiu	$t2,$t1,0x60	# if digit < 6, okay
	bnez	$t2,tiend
	nop
	addiu	$t0,$t0,0xa0	# adjust digit
	andi	$t1,$t0,0xf00	# check minute digit
	sltiu	$t2,$t1,0xa00	# if digit < a, okay
	bnez	$t2,tiend
	nop
	addiu	$t0,$t0,0x600	# adjust digit
	andi	$t1,$t0,0xf000	# check last digit
	sltiu	$t2,$t1,0x6000	# if digit < 6, okay
	bnez	$t2,tiend
	nop
	addiu	$t0,$t0,0xa000	# adjust last digit
tiend:	sw	$t0,0($a0)	# save updated result
	jr	$ra		# return
	nop

  # you can write your code for subroutine "hexasc" below this line
  #
time2string:
	add $t0, $a1, $0 #load timeStr into $t0
	sll $t0, $t0, 16 #null left of 16bits
	srl $t0, $t0, 16
	
	# zero out everything except valued bits
	andi $t1, $t0, 0x000F #sec1
	andi $t2, $t0, 0x00F0 #sec2
	andi $t3, $t0, 0x0F00 #min1
	andi $t4, $t0, 0xF000 #min2
	
	# Move them all down
	srl $t1, $t1, 0
	srl $t2, $t2, 4
	srl $t3, $t3, 8
	srl $t4, $t4, 12
	
	# Let's send them to hexasc and fill in the memory!
	# Oh right, it doesn't matter which way we do it, gotta fix the indices x)
	
	PUSHALL
	add $a0, $t4, $0
	jal hexasc
	POPALL
	sb $v0, 0($a0)
	
	PUSHALL
	add $a0, $t3, $0
	jal hexasc
	POPALL
	sb $v0, 1($a0)
	
	#Add colon
	la $t0, colonASCII
	sb $t0 2($a0)
	
	PUSHALL
	add $a0, $t2, $0
	jal hexasc
	POPALL
	sb $v0, 3($a0)
	
	PUSHALL
	add $a0, $t1,$0
	jal hexasc
	POPALL
	sb $v0, 4($a0)

	# NUL
	addi $t0, $0, 0x00
	sb $t0, 5($a0)
	
	jr $ra
	
hexasc:
	# Remove all bits but the 4 LSB saved to t0 from a0, ignore checking for negative number
	sll $t0, $a0, 28
	srl $t0, $t0, 28
	li $t1, 0x09
	ble $t0, $t1, number 
	
letter:
	# Remove so we get back to 0-9 range
	addi $t0, $t0, -0x0A
	# Add on 0x41 to start at 'A'
	addi $t0, $t0, 0x41
	j finish 
number:
	# Add on 0x30 to start at '0'
	addi $t0, $t0, 0x30
	j finish
finish:
	li $v0, 0
	add $v0, $0, $t0
	jr $ra
	
delay:
	jr $ra
	nop