assembly - Address Out of Range. Hex to Decimal Mips -

i trying convert hex binary. stuck. storing bite returns error "address out of range". here code:

.data input: .word 0x12345678 buff: .space 40 la $a0, input la $a1, buff .text  move $t2, $a0      li $t1, 0  loop:     rol $t2, $t2, 1      , $t0, $t2, 1     add $t0, $t0, 48     move $a0, $t0     li $v0, 11     syscall     sb $a1, 0($a0) # runtime exception @ 0x00400228: address out of range 0x000000030     subi $t1, $t1, 1     bne $t1, 32, loop     jr $ra 

i found out during compilation mips turns hex decimal form, meaning 0x12345678 should change 305419896 , code should output binary of 00010010001101000101011001111000. instead, getting output of 00010000000000010000000000000000. if figuring out why address out of range , why hex doesn’t seem changing proper decimal during compile, appreciated. thank you.

update: have changed move $t2, $a0 lw $t2, 0($a0). m able correct binary representation. however, still receiving address out of range error on sb line.

your address out of range, because accessing wrong register.

sb $a0, 0($a1) store byte (48) memory buff.

similarly instruction move $t2, $a0 copies address of input 1 register another, when should access memory. lb $t2, ($a0) load first byte of input. lw read word , ld read double word.