[avr-gcc-list] Re: Patch for Win32 build of avr-gcc to support ATMega128

[Anton Erasmus]

Date sent:              Fri, 18 Jan 2002 14:12:51 +0100
From:                   Matthias Lange <address@hidden>
Organization:           Pro Design
To:                     Anton Erasmus <address@hidden>,
        "address@hidden" <address@hidden>
Subject:                Re: Patch for Win32 build of avr-gcc to support 
ATMega128

> This is a multi-part message in MIME format.
> --------------61C3DE1412940C7F140B15EC
> Content-Type: text/plain; charset=us-ascii
> Content-Transfer-Encoding: 7bit
> 
> Anton Erasmus wrote:
> > 
> > Hi,
> > 
> > It seems that quite a number of people are interested in compiling
> > for the ATMega128 without having to build the avr-gcc binaries with
> > proper ATMega128 support for themselves.
> > 
> > Attached is a zip file with the modified files I use to compile code
> > for the ATMega128 as well as a small example that shows using the
> > inp and outp macros to access ATMega128 I/O registers that cannot be
> > accessed with the "in" and "out" instructions.
> > 
> > The make1 and make2 files are modified versions of the Volker Oth
> > originals. These should be copied to avrgcc/include. mk128 is the
> > make file to make the example. Use make -fmk128 or use cc.bat.
> > m128test.c is the example c file. iomacros.h is a modified version
> > of the standard iomacros.h files. This should be copied to
> > avrgcc/avr/include. Only the inp and outp macros have been modified.
> > crtm128.o is the startup object file for the ATMega128. This is
> > assembled from the gcrt1.s file using the make file m128_crt.
> > ldscript.x is the linker script modified for the ATMega128. It also
> > adds a section "batram" which is external memory from 0x1100 to
> > 0x7FFF. This section is not initialised by the startup file. Hence
> > suitable for battery backed RAM. See the example C file on how to
> > declare a variable in this section.
> > 
> > Remember that the ATMega128 as shipped is in ATmega103
> > mode. One has to update the fuses to get it to run in ATMega128
> > mode.
> > 
> > I see no reason why these patches would not work for a Linux build
> > of avr-gcc.
> > 
> > Regards
> >    Anton Erasmus
> 
> 
> 
> Hi Anton,
> 
> I got it working, on Linux, thanks a lot !
> 
> This is my configuration : 
> 
>  binutils-2.11.2
>  gcc-3.0.2
>  avr-libc-20020115
> 
> I am using your crtm128.o, iomacros.h and the setting MCU = atmega128
> in my makefile.
> 
> In addition I made some changes to the iom128.h file to get
> compatibility with my atmega103 sources.
> 
> I did some changes to your iomacros.h too:
> 
> - cbi, sbi, bit_is_clear and bit_is_set are now working on PORTG too -
> I added outw() and inw() macros to access the extended 16Bit registers
> like TCNT3L/H
> 
> I am not sure if this is the best way and if it works on all MCUs. But
> anyway I have attached these files. Perhaps its useful for somebody
> else too.
> 
> Best regards
> 
> -Matthias Lange
>

Hi Matthias,

Thanks for the iomacros.h additions. 

If your compiler build accepts the mcu=atmega128 option, then it 
already has support for the atmega128. It should not be 
neccessary to manually link with  crtm128.o.

If I specify mcu=atmega128 on the Win32 binary build from 
avrfreaks.net, then I get the error: cc1.exe: MCU `atmega128' not 
supported

Regards
   Anton Erasmus


avr-gcc-list at http://avr1.org