TASM/MASM
.model small
.stack
.data
Message DB "Hello World!$"
.code
main proc
MOV DX,OFFSET Message
MOV AX,SEG Message
MOV DS,AX
MOV AH,9
INT 21h
MOV AX,4C00h
INT 21h
main endp
END main
Или ASM32/CPL32
BEGIN 100h ; for .COM file
MOV DX,Message
MOV AH,9
INT 21h
MOV AX,4C00h
INT 21h
Message:DB "Hello World!$"