Ok, so I suppose to debug the following code and I think I almosthave it. But I

Question

Ok, so I suppose to debug the following code and I think I almosthave it. But I can't figure out this last part.. I'll paste thecode then explain more:
At the marked line below I where Xspim aaand PCSpim (I tried both)gives me an error.. I'm not sure if I'm loading something into thecorrect register or not.. Then we have only had two classes so Idon't dont too much about Assembly yet..

If I'm not mistaken, I believe this code is suppose to read in astring of 8 number and then spit them right back out as singleintegers. Please Help, I WILL RATE..

Below is the code and this is the error I get..
The output is -1, which I'm assuming is the ascii_error, since whenI change the -1, to say -3 I get a -3.. My Spim tells me this..

 # Beginning of code
.data


prompt: .asciiz " Enter a string of numbers up to 8 characters: "
newln:  .asciiz " "
str:    .space 10
.text
#.globl main
main:
#__start:
li    $v0, 4
la    $a0, prompt               

syscall                         



li    $v0, 8                    

li    $a1, 10                   

la    $a0, str                  

syscall                         



jal ascii_loop                  





li    $v0, 1                    

syscall                         

#done                            



ascii_loop:                             

li    $t4, 10                   

addi  $t2, $0, 0                

move  $t1, $a0                  





loop:   

           <<<---- Error happens here 

la      $t3, newln

beq   $t1, $t3, ascii_end                                               

li    $t3, '0'                  

blt   $t1, $t3, ascii_error     

li    $t3, '9'                                                          

bgt   $t1, $t3, ascii_error

addi  $t3, $t1, -48
mul   $t2, $t2, $t4
add   $t2, $t3, $t2
addi  $t0, $t0, 1
b     loop
ascii_error:
li    $t2, -1
ascii_end:
move  $a0, $t2
jr    $ra 

Explanation / Answer

.data
prompt: .asciiz " Enter a string of numbers up to 8 characters:"
newln: .asciiz " "
str: .space 10
.text
main:
li $v0, 4
la $a0, prompt
syscall                        

li $v0,8                   
li    $a1,10                  
la    $a0,str                 
syscall                        

jalascii_loop                 

li    $v0,1               
syscall                                           

ascii_loop:                            
li    $t4,10                  
addi $t2, $0,0               
move $t0,$a0              # t0 now has the address of the inputbuffer


loop:  
lb     $t1,($t0)                          #load the 1st character input intot1
la $t3,newln                              #load address of newln into t3
beq   $t1, $t3,ascii_end        #are they the same?   -comparing address and value doesn't make sense???                              
li    $t3,'0'                 
blt   $t1, $t3, ascii_error    
li    $t3,'9'                 
bgt   $t1, $t3, ascii_error
addi $t3, $t1, -48
mul   $t2, $t2, $t4
add   $t2, $t3, $t2
addi $t0, $t0, 1
b     loop

ascii_error:
li    $t2, -1

ascii_end:
move $a0, $t2
jr    $ra

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