So for my assembly code (MIPS using MARS), I have to prompt the user to enter a

Question

So for my assembly code (MIPS using MARS), I have to prompt the user to enter a number between 2 and 36 to signify which base the number they want to convert is in. Then I prompt the user to enter the number they want to convert. Then I prompt the user to enter a number between 2 and 36 to signify which base they want to convert a number to. Then I'm supposed to take the number and convert it to the new base they specified and print that number.

[For clarification, I am using a code from my previous project that was similar, but the user would imput their number only in decimal (base 10) rather than any number from any base.]

My code keeps breaking and I have no idea what's wrong. The code is due at 5 PM CST.

.text
.globl main   
  
main:
move $t0, $zero
move $t1, $zero
  
redoLoop:   

li $v0, 4
la $a0, prompt # print "enter old base"
syscall
  
li $v0, 5   
syscall
move $t0, $v0 #store in $t0

li $v0, 4
la $a0, convert # print "enter number to convert"
syscall
  
li $v0, 5
syscall # take number entered and store in inbuf
la $v0, inbuf
  
li $v0, 4
la $a0, base # print "enter new base"
syscall
  
li $v0, 5
syscall
move $t1, $v0 # store new base in $t1
  
#------ take number from buffer one byte at time
move $t2, $zero # set number storage = to 0
move $t3, $zero # offset into the buffer array
top:
lb $a0, inbuf($t3) # loads index of inbuf to $a0
beq $a0, $zero, out # exit loop when null char found
beq $a0, 10, out # exit loop if new line found
#------ subtract 48 or 55
blt $a0, 58, nineorless
blt $a0, 91, alphabet

nineorless:
subi $a0, $a0, 48
add $t2, $t2, $a0
j increment
alphabet:
subi $a0, $a0, 55
add $t2, $t2, $a0
j increment

increment:
addi $t3, $t3, 1
beq $a0, $zero, out # exit loop when null char found
beq $a0, 10, out # exit loop if new line found
mul $t2, $t2, $t0 # if another character found multiply number by old base
j top
out:


li $v0, 4 # print_string
la $a0, enter
syscall
  
jal findBase
  
############################################
findBase:

# la $a0, ($t2)
# move $t2, $a0
move $t4, $zero
rem $t4, $t2, $t1
div $t2, $t2, $t1
#addi $s6, $s6, 1
#addi $a2, $a2, -1
  
bgt $t4, 9, great
ble $t4, 9, less
return:   
bge $t2, 1, findBase
  
li $v0, 4 # print_string
la $a0, outbuf
syscall
  
  
  
addi $sp, $sp, -4   
sw $ra, 0($sp)
jal spacePrint
lw $ra, 0($sp)
addi $sp, $sp, 4
  
addi $sp, $sp, -4   
sw $ra, 0($sp)
jal resetBuf
lw $ra, 0($sp)
addi $sp, $sp, 4

addi $a1, $a1, 4   
addi $t0, $t0, 1
move $a2, $s1   
blt $t0, 10, findBase
  
move $a0, $zero
move $t4, $zero
move $t5, $zero
move $t7, $zero
move $t6, $zero
la $a1, inbuf
la $a2, ($s1)
jr $ra
  
great:
   addi $t3, $t3, 55
   sb $t3, outbuf($a1) #stores remainer in outbuf ## not sure about $a2
   addi $a1, $a1, 1
   j return
less:
addi $t4, $t4, 48
sb $t4, outbuf($a1) #stores remainder in outbuf ## not sure about $a2
addi $a1, $a1, 1
   j return
spacePrint:
lb $a0, outbuf($a3)
beq $a0, '', lap
li $v0, 11
syscall
lap:
addi $a3, $a3, 1
ble $a3, 10, spacePrint
end:
move $a3, $zero
move $s6, $zero
jr $ra   

resetBuf:
sb $zero, outbuf($t1)   
addi $t1, $t1, 1   
blt $t1, 10, resetBuf   
move $t1, $zero
jr $ra

li $v0, 4
la $a0, again
syscall

li $v0, 8 # read string
syscall   
la $a0, redoEntry # original input is in userEntry
  
move $t9, $zero
lb $a0, redoEntry($t9) # char to print is in $a0
beq $a0, 121, redoLoop

li $v0, 10 # using service 10, terminate
syscall  
  
  
# ------------------------------------------------------
.data # beginning of data area
prompt:
.asciiz "Enter the old base (2 - 36) - "
convert:
.asciiz " Enter the number to be converted - "
base:
.asciiz " Enter the new base - "
again:
.asciiz " Again (y or n) ? "
redoEntry:
.word 0
enter:
.asciiz " "
outbuf:
.space 36
inbuf:
.space 36
# ------------------------------------------------------

Explanation / Answer

You're missing a .text directive. That should probably go after your newline line and before main:.

You have a $ao where you probably want a $a0 near the end of the program.

You didn't ever print str3 - you need to add:

la $a0,str3 #address of str3 syscall

after your li $v0,4 #system call code for print string line.

You should make sure to add an exit syscall at the end of your program:

li $v0,10 syscall

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