Hi all,

Can anyone tell me whitch compiler should i use to generate Thumb code ?
I am using ARM-ELF-GCC for windows ( cygwin ) but it seems to genarate only ARM code !

Thanks in advanced

Hi Overcast,
the arm-elf-gcc compiler can also generate thumb code.
There are several possibilities how to make this.

For C Files you can use the following compiler options:
-mthumb assemble Thumb code
-mthumb-interwork support ARM/Thumb interworking

Use "arm-elf-gcc --target-help" to get a list for the special arm command line options.

For Assembler files you can use the following (insode the file):
.arm - for ARM 32 code (or .code 16)
.thumb - forthumb code (.code 32)

For C-files it is also possible to use the following preprocessor macros (use the attribute key word for this):
__thumb
__arm

But i do not know how to make this in detail. If you can't get i running, please mail again.

Hint: Interrupts use alwys ARM (32 bit) code)

Best regards,
Edi

Hi edi ...

Are you shure that the arm-elf-gcc for windows ( cygwin ) works fine generating thumb code ? As you wrote , I tried:

-mthumb assemble Thumb code
-mthumb-interwork support ARM/Thumb interworking

but neigther were recognized ... i tried the --help options but got no response

also I tried "arm-elf-gcc --target-help" but the response was :
arm-elf-gcc: No input files

$ arm-elf-gcc --version
2.95.3


Thanks for the quiqly answer !

Hi,
yes i am sure that the gcc windows version supports arm thumb. I am not sure if it possible to disable this during the build of the compiler.

This means to me, that something goes wrong with the option. Be sure that you have done:
arm-elf-gcc --target-help

I have check this on a cygwin based gcc version 3.3. This version i have compiled at my own.

Best regards,
Edi

Ok edi ...

I will try harder !

Thank you verry much