x86 NASM Assembly - Problems with Input
%include "system.inc"

section .data
    greet:      db 'Hello!', 0Ah, 'Please enter a word or character:', 0Ah
    greetL:     equ $-greet     ;length of string
    inform:     db 'I will now repeat this until you type it back to me.', 0Ah
    informL:    equ $-inform
    finish:     db 'Good bye!', 0Ah
    finishL:    equ $-finish
    newline:    db 0Ah
    newlineL:   equ $-newline


section .bss

input: resb 40  ;first input buffer
check: resb 40  ;second input buffer

section .text

    global _start
_start:


greeting:
    mov eax, 4
    mov ebx, 1
    mov ecx, greet
    mov edx, greetL %include "system.inc"

    section .data
        greet:      db 'Hello!', 0Ah, 'Please enter a word or character:', 0Ah
        greetL:     equ $-greet     ;length of string
        inform:     db 'I will now repeat this until you type it back to me.', 0Ah
        informL:    equ $-inform
        finish:     db 'Good bye!', 0Ah
        finishL:    equ $-finish
        newline:    db 0Ah
        newlineL:   db $-newline


    section .bss

    input: resb 40  ;first input buffer
    check: resb 40  ;second input buffer

    section .text

        global _start
    _start:


    greeting:
        mov eax, 4
        mov ebx, 1
        mov ecx, greet
        mov edx, greetL
        sys.write

    getword:
        mov eax, 3
        mov ebx, 0
        mov ecx, input
        mov edx, 40
        sys.read

        sub eax, 1  ;remove the newline
        push eax    ;store length for later

    instruct:
        mov eax, 4
        mov ebx, 1
        mov ecx, inform
        mov edx, informL
        sys.write

        pop edx     ;pop length into edx
        mov ecx, edx    ;copy into ecx
        push ecx    ;store ecx again (needed multiple times)

        mov eax, 4
        mov ebx, 1
        mov ecx, input
        sys.write

        mov eax, 4  ;print newline
        mov ebx, 1
        mov ecx, newline
        mov edx, newlineL
        sys.write

        mov eax, 3  ;get the user's word
        mov ebx, 0
        mov ecx, check
        mov edx, 40
        sys.read

        xor eax, eax

    checker:
        mov ebx, check
        mov ecx, input
        cmp ebx, ecx    ;see if input was the same as before

        jne loop    ;if not the same go to input again
        je done     ;else go to the end
        pop edx
        mov ecx, edx
        push ecx
        mov eax, 4
        mov ebx, 1
        mov ecx, check
        sys.write   ;repeat the word

        mov eax, 4
        mov ebx, 1
        mov ecx, newline
        mov edx, newlineL
        sys.write



    loop:
        mov eax, 3  ;replace new input with old
        mov ebx, 0
        mov ecx, check
        mov edx, 40
        sys.read

        jmp checker

    done:

        mov eax, 1
        mov ebx, 0
        sys.exit
    sys.write

getword:
    mov eax, 3
    mov ebx, 0
    mov ecx, input
    mov edx, 40
    sys.read

Hello!
Please enter a word or character:
Nick
I will now repeat this until you type it back to me.
Nick
(I input) Magerko
(I get) M
(I input)Nick
(I get)
(I input)Nick
(I get)

checker:
    mov ebx, check  ; Moves the *address* of check into ebx
    mov ecx, input  ; Similarly for input
    cmp ebx, ecx    ; Checks if the addresses are the same (they never are)

mov eax, [input_len]
    cmp eax, [check_len]
    jne loop       ; Strings of different length, do loop again
    mov ebx, check
    mov ecx, input
.checkloop:
    mov dl, [ebx]  ; Read a character from check
    cmp dl, [ecx]  ; Equal to the character from input?
    jne loop       ; Nope, jump to `loop`
    inc ebx        ; Move ebx to point at next character in check
    inc ecx        ; and ecx to next character in input
    dec eax        ; one less character to check
    jnz .checkloop ; done?

    ; the strings are equal if we reach this point in the code
    jmp done

jne loop    ;if not the same go to input again
je done     ;else go to the end
pop edx   ; Will never be reached!