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Avr系列单片机反汇编器源代码.GCC编译

README
vAVRdisasm - Version 1.2 - 2007/01/06
Vanya A. Sergeev - <[e-mail]>
================================================================================
Table of Contents

1. ABOUT vAVRdisasm
2. LICENSE
3. COMPILING vAVRdisasm
4. USING vAVRdisasm
5. Ghetto Address Labels
6. Shortcomings
7. Source Code
8. Sample Disassembly Outputs  
================================================================================

1. ABOUT vAVRdisasm
================================================================================
vAVRdisasm is an AVR program disassembler. It supports all 136 AVR instructions 
as defined by the Atmel AVR Instruction Set, revision 0856E-AVR-11/05.

This single-pass disassembler can handle Atmel Generic, Intel HEX8, and Motorola 
S-Record formatted files containing valid AVR program binaries.

vAVRdisasm features a handful of formatting options, including:
 - Printing the instruction addresses alongside disassembly, enabled by default
 - Printing of the destination comments of relative branch/jump/call
   instructions, enabled by default
 - Ghetto Address Labels (see "Ghetto Address Labels" section)
 - Formatting data constants in different bases (hexadecimal, binary, decimal)
 - .DW data word directive for data not recognized as an instruction during
   disassembly.

vAVRdisasm should work on most *nix platform, including a Cygwin environment.
vAVRdisasm was written in C by Vanya A. Sergeev - <[e-mail]>, and 
tested with the GNU C Compiler.

2. LICENSE
================================================================================
vAVRdisasm is released under the GNU General Public License.
    You should have received a copy of the GNU General Public License
    along with this program; see the file "COPYING".  If not, visit
    http://www.gnu.org or write to the Free Software Foundation, Inc.,
    59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

3. COMPILING vAVRdisasm
================================================================================
Simply by running,
$ make
 in the vAVRdisasm project directory should compile vAVRdisasm on most
*nix systems, including a Cygwin environment. The Makefile is configured to use GCC to compile vAVRdisasm.
vAVRdisasm should have no problem being compiled with "gmake".

4. USING vAVRdisasm
================================================================================
vAVRdisasm prints its disassembly output to stdout.

* File Input:
	For most purposes, just type
	 $ ./vavrdisasm <AVR program file>
	Example:
	 $ ./vavrdisasm sampleprogram.hex

	vAVRdisasm will auto-recognize Atmel Generic, Intel HEX8, and Motorola 
	S-Record files by their file extensions, but if it fails to do so, use 
	the the -t or --file-type option to specify the file format.
	Example:
	 $ ./vavrdisasm -t generic sampleprogram

	The file type argument to the option can be "generic", "ihex", or 
	"srecord" for Atmel Generic, Intel HEX8, or Motorola S-Record formatted 
	files, respectively.

* Options --data-base-...
	vAVRdisasm will default to formatting data constants in base 
	hexadecimal. However, data constants can be represented in a different 
	base with one of the following options: --data-base-hex, 
	--data-base-bin, and --data-base-dec.

* Options --no-...
	By default, vAVRdisasm will print the instruction addresses alongside 
	disassembly and destination comments for relative branch, jump, and call
	instructions. These formatting options can be disabled with the 
	--no-addresses and --no-destination-comments options.

* Options -l or --address-label	
	For usage information on the -l or --address-label option see the 
	"Ghetto Address Labels" section.

* Options -h or --help, -v or --version
	The -h or --help option will print a brief usage summary, including 
	supported program options and file types.
	The -v or --version option will print the program's version number.

If you encounter any program bugs or problems, please notify the program
author by email: Vanya A. Sergeev - <[e-mail]>.

5. Ghetto Address Labels
================================================================================
vAVRdisasm supports a unique formatting feature: Ghetto Address Labels, which 
few, if not any, single-pass disassemblers implement.

With the -l or --address-label option and a supplied prefix, vAVRdisasm
will print a label containing the (ideally) non-numerical supplied prefix 
and the address of the disassembled instruction at every instruction. Also, 
all relative branch, jump, and call instructions will be formatted to jump
to their designated address label.

This feature enables direct re-assembly of the vAVRdisasm's disassembly.
This can be especially useful for quick modification of the AVR program assembly
code without having to manually format the disassembly or adjust the relative
branch, jump, and call distances with every modification to the disassembly.

The -l or --address-label option overrides the default printing of the
addresses alongside disassembly. Destination comments can still be used.

Example:
$ ./vavrdisasm -l "A_" sampleprogram.hex
vAVRdisasm's disassembly will include address labels that will look like this
A_0000:. For sample disassembly outputs by vAVRdisasm, see the
"Sample Disassembly Outputs" section.

6. Shortcomings
================================================================================
vAVRdisasm does not disassemble and display alternate versions of the same
encoded instruction (i.e. showing "eor" in additon to "clr"). This technically
means that the "cbr" instruction can never be displayed in the disassembly 
because the "andi" instruction precedes it in priority.
vAVRdisasm does not display the original opcode of the disassembled instruction.
The original opcode can be convenient for some disassembled instructions that
were actually meant to be data words (.DW).
These feature do not affect the accuracy of the disassembler's output, and 
may be supported in future versions of vAVRdisasm.

7. Source Code
================================================================================
vAVRdisasm's source code is heavily commented, because this disassembler was
also a personal learning project of the author.
Operand prefixes (such as "R" for register operands or "$" for data operands)
can be customized in the format_disasm.h header file. 
Field width spacing of the addresses printed alongside disassembly, and the
destination relative address comments can be customized in the ui_disasm.c
source file.
The output file (default is stdout) can be changed in ui_disasm.c source file.
vAVRdisasm uses libGIS, a free Atmel Generic, Intel HEX8, and Motorola S-Record 
Parser Library to parse formatted files containing AVR program binaries. libGIS
is available for free under a Public Domain license at:
http://www.frozeneskimo.com/electronics/libgis-free-atmel-generic-intel-hex-and-motorola-s-record-parser-library/
libGIS is compiled into vAVRdisasm--it does not need to be obtained separately.

8. Sample Disassembly Outputs
================================================================================
These disassembly samples, produced by vAVRdisasm, are of the program code in 
the "Novice's Guide to AVR Development" article of the Atmel Applications
Journal.

$ ./vavrdisasm sampleprogram.hex 
   0:   rjmp .0         ; 0x2
   2:   ser R16
   4:   out $17, R16
   6:   out $18, R16
   8:   dec R16
   A:   rjmp .-6        ; 0x6

$ ./vavrdisasm --no-destination-comments sampleprogram.hex
   0:   rjmp .0
   2:   ser R16
   4:   out $17, R16
   6:   out $18, R16
   8:   dec R16
   A:   rjmp .-6

$ ./vavrdisasm --no-addresses sampleprogram.hex
rjmp .0         ; 0x2
ser R16
out $17, R16
out $18, R16
dec R16
rjmp .-6        ; 0x6

$ ./vavrdisasm --no-addresses --no-destination-comments sampleprogram.hex
rjmp .0
ser R16
out $17, R16
out $18, R16
dec R16
rjmp .-6

$ ./vavrdisasm -l "A_" sampleprogram.hex

.org 0x000
A_000: rjmp A_002       ; 0x2
A_002: ser R16
A_004: out $17, R16
A_006: out $18, R16
A_008: dec R16
A_00A: rjmp A_006       ; 0x6

$ ./vavrdisasm -l "A_" --no-destination-comments sampleprogram.hex

.org 0x000
A_000: rjmp A_002
A_002: ser R16
A_004: out $17, R16
A_006: out $18, R16
A_008: dec R16
A_00A: rjmp A_006

The program sample above is modified slightly to illustrate vAVRdisasm's ability
to represent data constants in different bases.

$ ./vavrdisasm --data-base-bin sampleprogram2.hex
   0:   rjmp .0         ; 0x2
   2:   ser R16
   4:   out $17, R16
   6:   ldi R16, 0b00100011
   8:   out $18, R16
   A:   dec R16
   C:   rjmp .-6        ; 0x8