为什么我从这个nasm收到错误消息？

Question

我在Windows 7 32位上执行此操作时出错：

SECTION .data       ; data section
msg:    db "Hello World",10 ; the string to print, 10=cr
len:    equ $-msg       ; "$" means "here"
            ; len is a value, not an address

SECTION .text       ; code section
    global main     ; make label available to linker 
main:               ; standard  gcc  entry point

mov edx,len     ; arg3, length of string to print
mov ecx,msg     ; arg2, pointer to string
mov ebx,1       ; arg1, where to write, screen
mov eax,4       ; write sysout command to int 80 hex
int 0x80        ; interrupt 80 hex, call kernel

mov ebx,0       ; exit code, 0=normal
mov eax,1       ; exit command to kernel
int 0x80        ; interrupt 80 hex, call kernel

程序退出但没有输出。为什么我会收到此错误？