; -*- nasm -*-
; NASM macro file to allow the `bin' output format to generate
; simple .EXE files by constructing the EXE header by hand.
; Adapted from a contribution by Yann Guidon <whygee_corp@hol.fr>
%define EXE_stack_size EXE_realstacksize
%macro EXE_begin 0
ORG 0E0h
section .text
header_start:
db 4Dh,5Ah ; EXE file signature
dw EXE_allocsize % 512
dw (EXE_allocsize + 511) / 512
dw 0 ; relocation information: none
dw (header_end-header_start)/16 ; header size in paragraphs
dw (EXE_absssize + EXE_realstacksize) / 16 ; min extra mem
dw (EXE_absssize + EXE_realstacksize) / 16 ; max extra mem
dw -10h ; Initial SS (before fixup)
dw EXE_endbss + EXE_realstacksize ; Initial SP (1K DPMI+1K STACK)
dw 0 ; (no) Checksum
dw 100h ; Initial IP - start just after the header
dw -10h ; Initial CS (before fixup)
dw 0 ; file offset to relocation table: none
dw 0 ; (no overlay)
align 16,db 0
header_end:
EXE_startcode:
section .data
EXE_startdata:
section .bss
EXE_startbss:
%endmacro
%macro EXE_stack 1
EXE_realstacksize equ %1
%define EXE_stack_size EXE_bogusstacksize ; defeat EQU in EXE_end
%endmacro
%macro EXE_end 0
section .text
EXE_endcode:
section .data
EXE_enddata:
section .bss
alignb 4
EXE_endbss:
EXE_acodesize equ (EXE_endcode-EXE_startcode+3) & (~3)
EXE_datasize equ EXE_enddata-EXE_startdata
EXE_absssize equ (EXE_endbss-EXE_startbss+3) & (~3)
EXE_allocsize equ EXE_acodesize + EXE_datasize
EXE_stack_size equ 0x800 ; default if nothing else was used
%endmacro
my problem was:
(header_end-header_start)/16 why to /16
dw -10h ; Initial SS why is -10h
EXE_acodesize equ (EXE_endcode-EXE_startcode+3) & (~3) why to add 3 and & (~3)
anybody can tell what I show?
thanks!
