Re: Porting Newlib to Microchip's dsPIC series

[Leo Singer <doc dot aronnax at gmail dot com>]

Oops, I meant to send this to the Newlib mailing list.

Leo

On Sun, Feb 1, 2009 at 2:05 PM, Leo Singer <doc.aronnax@gmail.com> wrote:
> Dear Karolina,
>
> I have also patched most of the source files in libnosys, giving them
> __attribute__ ((weak)) so that routines like open, read, write, close,
> and lseek can be overridden by user code just as with the stock
> Microchip standard library.
>
> Can you find out if "printf" is defined anywhere in the libraries you
> made?  If you go into the library containing the .a files, you can use
> the following command to find out:
>
> find . -name "*.a" -exec pic30-nm {} \; | grep '_printf'
>
> Thanks,
> Leo
>
> On Sun, Feb 1, 2009 at 1:42 PM, Karolina <karolina.lindqvist@kramnet.se> wrote:
>> lördagen den 31 januari 2009 skrev Leo Singer:
>>> Hey,
>>>
>>> I am porting Newlib to Microchip's line of 16-bit microcontrollers (I
>>> am using a dsPIC33FJ256GP710).  The compiler is invoked using the name
>>> "pic30-gcc".  I have some platform specific implementations of things
>>> like brk, sbrk, etc.  Where should I put those?
>>>
>>> I put them in "newlib/libc/sys/pic30", and I think that I made my
>>> Automake and Autoconf files correctly (though it's my first time
>>> actually editing automake or autoconf files), but the source files
>>> that I added are not getting compiled.
>>>
>>> My "setjmp" and "longjmp", which I have placed in
>>> "newlib/libc/machine/pic30" are correctly getting built and linked.
>>>
>>> Thanks,
>>> Leo
>>
>>
>> I am trying exactly the same right now. I got the whole thing to build without
>> error, but now I got a little bit stuck with gcc, to get it to use the
>> correct paths for include/lib files etc. I got more work there than I
>> bargained for.
>>
>> And then I am not sure if not newlib gives just too much bloat, and it would
>> be better to use unix v7 libs, or something.
>>
>> Some things with newlib I find confusing. Some systems put system files in
>> libgloss/<systemname>, and others in libc/sys/<systemname>
>> I put them in libc/sys/pic30
>>
>> Files I have patched so far:
>> newlib/libc/include/machine/ieeefp.h
>> newlib/libc/include/machine/setjmp.h
>> newlib/libc/include/sys/config.h
>> newlib/libc/include/sys/stdio.h
>> newlib/libm/machine/configure.in
>> config/mt-pic30
>> config.sub
>> newlib/configure.host
>> newlib/libc/machine/configure.in
>>
>> But apart from making a clean build, it has to be integrated with all the
>> quirks of the PIC30 and tried out and get to work also. That is probably the
>> tough part.
>>
>> Karolina
>>
>>
>