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Printing output

Printing output

Printing output

(OP)
First let me say, I'm very, very, (very) new at Assembly.  I'm using NASM on Linux.  I have an undeclared variable that I'm putting numbers I'm getting from user input.  

When I try to output the numbers, I'm not getting anything.  I'm not sure what I'm doing wrong.  Could anyone help me with this?

I realize I still need to work on getting the input down, but for now, I'd be happy to get it to print what I want and that is primarily the values I've inputted into the variable "sum".  

;=====================================================
section .data                            ; DECLARED VARIABLES
;=====================================================

big        db    "bigger than 50", 0xA
blen     equ    $ - big                              ; length of string "big"
small    db    "smaller than 51", 0xA
slen        equ    $ - small                         ; length of string "small"
greet    db    "Enter any two digit number", 0xA
glen        equ    $ - greet                         ; length of string "greet"

;=====================================================
section .bss                            ; UNDECLARED VARIABLES
;=====================================================

chr       resw     2              ; reserve uninitialized data
sum     resw     2              ; reserve for a converted number
num     resw     1              ; reserve for a converted number

;=====================================================
section .text                            ; CODE TEXT
;=====================================================

global main

main:
    mov        ax, 0
    mov        [sum], ax

;============================
         ;loop begins here
;============================
intro:
    mov     eax, 4               ; system call number (sys_write)
    mov     ebx, 1               ; first argument:    file handle (stdout)
    mov     ecx, greet        ; second argument:   pointer to num
    mov     edx, glen         ; third argument:  length of string
    int 0x80
beg:
    mov        eax, 3        ; system call number (sys_read)
    mov        ebx, 0        ; first argument: file handle (stdin)
    mov        ecx, chr        ; second argument: pointer to character
    mov        edx, 2        ; third argument: length
    int     0x80            ; call kernel

    cmp        byte [chr], 0x30
    jb    e1                ; char < '0', so get out
    cmp        byte [chr], 0x39
    ja    e1            ;mov    ecx, sum
    ;mov    edx, 5    ; char > '9', so get out

    mov     ax, [sum]
    imul    ax, 10
    mov        bx, 0
    mov        bl, [chr]
    sub        bl, 0x30
    add        ax, bx
    mov        [sum], ax
    jmp    beg

e1:
    cmp        word [sum], 50
    jb    smt6            ; smaller than 6
    mov        ecx, big
    mov        edx, blen
    jmp    e2

smt6:
    mov        ecx, small
    mov        edx, slen

e2:
    mov        eax, 4        ; system call number (sys_write)
    mov        ebx, 1        ; first
    int     0x80            ; call kernel

    mov        eax, 4        ; system call number (sys_write)
    mov        ebx, 1        ; first
    mov    ecx, sum
    ;mov    edx, 1
    int     0x80            ; call kernel

    mov    eax, 1            ; system call number (sys_exit)
    mov    ebx, 0            ; exit number
    int     0x80            ; call kernel

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