iNES header

 NES ELITE GAME SOURCE (iNES HEADER)

 NES Elite was written by Ian Bell and David Braben and is copyright D. Braben
 and I. Bell 1991/1992

 The code on this site has been reconstructed from a disassembly of the version
 released on Ian Bell's personal website at http://www.elitehomepage.org/

 The commentary is copyright Mark Moxon, and any misunderstandings or mistakes
 in the documentation are entirely my fault

 The terminology and notations used in this commentary are explained at
 https://www.bbcelite.com/terminology

 The deep dive articles referred to in this commentary can be found at
 https://www.bbcelite.com/deep_dives


 This source file produces the following binary file:

   * header.bin


 INCLUDE "1-source-files/main-sources/elite-build-options.asm"

 _NTSC = (_VARIANT = 1)
 _PAL  = (_VARIANT = 2)

 ELITE iNES HEADER

 Produces the binary file header.bin.


 CODE% = $8000          ; The address where the code will be run

 LOAD% = $8000          ; The address where the code will be loaded

 ORG CODE%


       Name: iNES header                                             [Show more]
       Type: Variable
   Category: Start and end
    Summary: The iNES header for running in an emulator
  Deep dive: Splitting NES Elite across multiple ROM banks
    Context: See this variable on its own page
 References: No direct references to this variable in this source file


 EQUS "NES"             ; Bytes #0 to #2 = identification string for iNES file

 EQUB $1A               ; Byte #3 = identification string terminator

 EQUB 8                 ; Byte #4 = 8 pages of 16K ROM = 128K

 EQUB 0                 ; Byte #5 = 0 = board uses CHR RAM

 EQUB %00010010         ; Byte #6 = mapper and WRAM configuration
                        ;
                        ;   * Bit 1 set = Cartridge contains battery-backed RAM
                        ;                 at $6000 to $7FFF
                        ;
                        ;   * Bits 4-7 = mapper number, %0001 = MMC1

 EQUB 0                 ; Bytes #7 to #15 are zero and have no effect
 EQUD 0
 EQUD 0

 Save header.bin


 PRINT "S.header.bin ", ~CODE%, " ", ~P%, " ", ~LOAD%, " ", ~LOAD%
 SAVE "3-assembled-output/header.bin", CODE%, P%, LOAD%