Not getting correct input form either scanf or printf in Nasm assembly program with menu -

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in following, i'm trying make user enters n , prompte enter integer. got part working. i've spent few hours trying next part working. after enter integer, goes menu. debugging purposes, if enter f should display number entered. however, when entering n, 3, f, displays 21505. 

;nasm -f elf64 fib.asm -o fib.o ;gcc -s -masm=intel fib.c -o fib.s ;./fib         bits 64     global  main     extern  puts     extern  printf     extern  scanf        extern  get_kb    section.data  errormsg:   db  'invalid input. enter n,f, or x',0x0d,0x0a,0  numequalsmsg:   db  'number equals: '  lc2:    db  "%d",0   menuprompt: db  0x0d,0x0a,'enter n enter integer 0 20',0x0d,0x0a,'enter f display first n+1 numbers (beginning zero) on console',0x0d,0x0a,'enter x quit program',0x0d,0x0a,0   choicemsg:  db  "your choice: ",0  lc5:    db  "%d",0   enterintmsg:    db  "enter , integer 0-20: ",0   enternummsg:    db  'enter valid number between 0 , 20',0x0d,0x0a,0   lc8:    db  " , ",0 lc9:    db  'success!',0x0d,0x0a,0 lc10:   db  'in l10!',0x0d,0x0a,0        lc11:   db  'in l12!',0x0d,0x0a,0  lc13:   db  'in compare 0 section',0x0d,0 value:  db  0 choice: db  1   .code main:     ;function setup      ;push   rbp     ;mov    rbp, rsp     ;sub    rsp, 16     call menu  menu:     ;print menu      mov edi, menuprompt     call    puts            ;display menu     mov edi,choicemsg     ;mov    eax, 0     ;call   printf          ;display "your choice:"      call puts     call    get_kb     mov bl, al     cmp bl, 'n' ;n     je  read_int_new     cmp bl, 'f' ;f     je  fib     cmp bl, 'x' ;x     je  correct     ;leave     ;ret      jmp menu     ret      correct:     mov edi, lc9     mov eax,0     call    printf     jmp     menu     ;leave       ;ret  entered_n:     call    read_int_new     ;jmp    correct      jmp menu     ;leave     ;jmp    menu   read_int:     mov edi, enterintmsg     mov eax,0     call    printf                ;mov    rdi, [lc5]     ;mov    rsi, [value]     ;xor    eax,eax      ;add    esp,4       ;remove parameters     ;push   rsi     ;push   rdi       ;push   rbp     ;mov    rax,0     ;mov    rdi, lc5     ;mov    rsi, value     push value     push lc5     call    scanf     add esp, 8      ;mov eax, value     push value     push lc5     call printf     add esp,8     ;pop    rbp     ;jmp    correct      ;mov cl, [value]     ;jmp    menu     ;leave     ret       ;leave    read_int_new:     ;push   rbp     ;mov    rbp, rsp     ;sub    rsp, 16       mov edi, enterintmsg    ;display "enter integer 0-20: "     mov eax, 0     call    printf      ;lea    rax, [value]     ;mov    rsi, rax     ;mov    edi, lc5     ;mov    eax, 0     ;call   scanf               ;get user input     ;mov    ebx, [value]      push value     push lc5         call scanf     mov esi, [value]      mov edi, lc9            ;test see if got here     mov eax, 0     call    printf         ;test   ebx, ebx            ;compare 0 (eax-eax=0)     ;js l9     ;mov    edi, lc9            ;test see if got here     ;mov    eax, 0     ;call   printf        ;mov    ebx, dword [rbp-4]     ;cmp    ebx, 20             ;jump if greater 20     ;jg l9     ;mov    edi, lc9            ;test see if got here     ;mov    eax, 0     ;call   printf            ;mov    ebx, dword [rbp-4]      ;else, jump l10     ;mov    edi, lc9            ;test see if got here     ;mov    eax, 0     ;call   printf           ;jmp    l10     ;leave       ;ret     jmp menu     fib:      mov eax, esi         mov edi, lc5     mov eax,0        ;mov eax, lc5     ;push [eax]      ;push value     ;push lc5         call printf    jmp menu

code not compile due missing get_kb. anyway, commented out code in read_int_new correct 1 except mov ebx, [value]. if change lc9 print number (use %d) can see reading works.

if fix fib replacing mov eax, esi (which makes no sense whatsoever) mov esi, [value] number correctly printed there too.

ps: learn use debugger.


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