main_hdr.asm

一款MP3 Player Firmware 的原代码,非常有参考价值

; MP3 Player, Main Program Header, http://www.pjrc.com/tech/mp3
; Copyright (c) 2000, PJRC.COM, LLC

; This program is free software; you can redistribute it and/or
; modify it under the terms of the GNU General Public License
; as published by the Free Software Foundation; either version 2
; of the License, or (at your option) any later version.

; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
; GNU General Public License for more details.

; You should have received a copy of the GNU General Public License
; along with this program; if not, write to the Free Software
; Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

; As a specific exception to the GPL, the executable object code built
; from this source code may be combined with hardware configuration data
; files.  A hardware configuration data file is a set of data that is
; transmitted to an intergrated circuit that is not a general purpose
; microprocessor or microcontroller, in order to establish its normal
; operation.  The process of combining the executable ojbect code built
; from the GPL licensed source code with the hardware configuration data
; shall be considered an aggregation of another work not based on the
; Program.  While the GPL does not restrict use of the program, any
; use restriction associated with the hardware configuration data (for
; example, that it only be used with particular hardware) shall apply
; to the combined file which includes a copy of the hardware configuration
; data.

; Contact: [e-mail]


.equ	app_location, 0x3000
.equ	startup_location, 0xEF00




.org	app_location
.db     0xA5,0xE5,0xE0,0xA5     ;signiture bytes
.db     35,255,0,0              ;id
.db     0,0,0,0                 ;reserved
.db     0,0,0,0                 ;reserved
.db     0,0,0,0                 ;reserved
.db     0,0,0,0                 ;reserved
.db     0,0,0,0                 ;user defined
.db     255,255,255,255         ;length and checksum (255=unused)
.db     "MP3 Player, Ver 0.6.90",0
.org	app_location+64		;executable code begins here

begin:
	;the linker MUST be configured to place the C application here!




; Auto Start When The Board Boots

.org    startup_location
.db     0xA5,0xE5,0xE0,0xA5     ;signiture bytes
.db     253,0,0,0               ;id
.db     0,0,0,0                 ;reserved
.db     0,0,0,0                 ;reserved
.db     0,0,0,0                 ;reserved
.db     0,0,0,0                 ;reserved
.db     0,0,0,0                 ;user defined
.db     255,255,255,255         ;length and checksum (255=unused)
.db     "Auto-Start",0
.org    startup_location+64	;executable code begins here

        ljmp    begin
        ret