输入没有显示在火星

如何解决输入没有显示在火星

它编译但在输出中，它没有显示任何我可以输入数字的地方。有什么想法吗？

.data
msg1:  .asciiz "array printing "
msg2:   .asciiz  "enter the number of rows: "
msg3:   .asciiz "enter the number of cols: "
msg4:   .asciiz "the value at the location is:  "
EOL:    .byte  '\n'
SPACES:   .asciiz "  "
MATRIX:   .word   1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25
.text
.globl main
main:
li   $v0,4
la  $a0,msg1
syscall
addiu $sp,$sp,-4
sw  $ra,0($sp)
jal  PRTMTX
lw  $ra,0($sp)
addiu  $sp,4
li $v0,10
syscall
PRTMTX:
la $s0,MATRIX
li $s1,1
li $s2,1
li $s6,5

TOPPRT:
addiu $t1,$s1,-1
addiu $t2,$s2,-1
li $t4,20
li $t5,4
mul $t1,$t1,$t4
mul $t2,$t2,$t5
add $s4,$s0,$t1
add $s4,$s4,$t2
li $v0,1
lw $a0,0($s4)
syscall
li $v0,4
la $a0,SPACES
syscall
li $t6,5
div $s2,$t6
mfhi $t6
beqz $t6,ENDROW
addiu $s2,1
j TOPPRT
ENDROW:  li $s2,1
li $v0,11
lb $a0,EOL
syscall
li $t6,5
div $s1,DONEPRT
addiu $s1,1
j TOPPRT
DONEPRT: 
jr $ra
PRTNUM:
move $t1,$a0
move $t2,$a1
addiu $t1,-1
li $t3,20
mul $t1,$t3
li $t3,4
mul $t2,$t3
la $s0,MATRIX
add $s0,$t1
add $s0,msg4
syscall
lw $a0,0($s0)
li $v0,1
syscall
EXIT:
    li $v0,10
    syscall