Question

Write a program that turns a 32-bit numeric value (e.g., 0xFFFFh) and converts it to a byte array such that it can be printed to the screen using a system call method. A loop is necessary for converting the numeric value to ASCII for output. Again, use a system call (e.g., int 80h) to print the value to the console. Calling external functions (e.g. printf) is not allowed. You may use the starter file attached to this assignment. PLEASE WRITE IN MASM!

Starter file:

; Assignment 5.3
; Prepare for output!(Challenge Assignment) - MASM(32 - bit)
; Copyright(c) 2017 Hall & Slonka

; Solution must use system call information from Chapter 10
; Use the CONSOLE subsystem(in project properties)
; Build, then run in a console window

.386
.MODEL FLAT, stdcall
.STACK 4096
GetStdHandle PROTO, nStdHandle:DWORD
WriteConsoleA PROTO,
hConsoleOutput : DWORD, ; output handle
        lpBuffer : PTR BYTE, ; pointer to buffer
        nNumberOfCharsToWrite : DWORD, ; size of buffer
        lpNumberOfCharsWritten : PTR DWORD, ; num bytes written
        lpReserved : DWORD; not used(NULL)
        ExitProcess PROTO, dwExitCode:DWORD

        .data
        bytesWritten DWORD 0                                                            ; for WriteConsoleA
        stdHandle DWORD 0                                                                       ; for WriteConsoleA
        val DWORD 0FFFFh                                                                        ; 65, 535 of possible 4, 294, 967, 295
        valArr BYTE 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0Ah, 0        ; 12 bytes
                                                                                                                ; 10 = max digits for 32 - bit number
                                                                                                                ; pre - load to 0 (non - print NULL)

        .code
        _main PROC

        print :
                                                                        ; get STDOUT handle
                push - 11                                       ; request STD_OUTPUT_HANDLE(-11)
                call GetStdHandle                       ; call WinAPI to get console handle
                mov stdHandle, eax                      ; save stdHandle

                push 0                                          ; reserved, push NULL
                push OFFSET bytesWritten        ; bytes written
                push 12                                         ; bytes to write
                push OFFSET valArr                      ; valArr address
                push stdHandle                          ; STD_OUPUT_HANDLE
                call WriteConsoleA                      ; call win api to write text to console

INVOKE ExitProcess, 0
_main ENDP
END

Answer 1