EmbDev.net

Forum: ARM programming with GCC/GNU tools Creating .elf from assembler


Creating .elf from assembler
von Jimmy (Guest)

Rate this post
• ▲ useful
▼ not useful 
Hello,

I am trying to create an .elf file from ARM assembly code needed for 
ARMulator.

But whenever I try to compile the code with arm-elf-gcc, I get a 'bad 
instruction' error for every sing line, but compiling the code under 
keil makes no problem.

The code:
1
   AREA    test, CODE, READWRITE

2
SWI_Exit    EQU &11

3
     ENTRY

4
    ADR    r0, A

5
  MOV    r1, #15

6
  STR    r1, [r0]

7
  SWI    SWI_Exit

8
A  =    0

9
  END


Neither arm-elf-gcc -o arm.elf arm.s
nor arm-elf-gcc -mthumb -Bstatic arm.s -o arm.elf
as suggested on the ARMulator's site are working.

I am already so desperate, as I can't find any proper tutorial or any 
more information on that.
So I would very much appreciate ur guys help, as I also need that for my 
uni coursework.

Cheers,
Jimmy

Report post Edit Move Thread sperren Anmeldepflicht aktivieren Anpinnen Delete topic Thread mit anderem zusammenführen Quote selected text Reply Reply with quote
Re: Creating .elf from assembler
von Krapao (Guest)

Rate this post
• ▲ useful
▼ not useful 
arm-elf-gcc (to be more specific the GNU Assembler) has another syntax 
than Keil Assembler. You would need to rewrite this KEIL assembler 
source code. Starting points are of course the Keil User Manual and the 
GNU Assembler Manual (gas).

Keil:
http://www.keil.com/support/man/docs/armasm/armasm_CEGFDGED.htm
http://www.keil.com/support/man/docs/armasm/armasm_Chdehaic.htm

gas:
http://sourceware.org/binutils/docs/as/

The line
> AREA test, CODE, READWRITE
will translate in something like
.section test, "awx"
or
.section .test, "awx"
If you look in such kind of code, you will find examples in the net e.g.
http://www.zap.org.au/elec2041-cdrom/unsw/elec2041/experiment5.pdf
that you can use as starter.

Hint: In order to have a section test, you need the proper linker 
control script with the memory layout as well! IMHO it's much easier to 
look for an assembler tutorial with usage of the GNU toolchain than 
struggling with two unkowns - Keil/GNU translation and ARM learning.

Report post Edit Delete Quote selected text Reply Reply with quote
Watch this topic | Disable multi-page view
Please log in before posting. Registration is free and takes only a minute.
Existing account
Do you have a Google/GoogleMail account? No registration required!
Log in with Google account
No account? Register here.