GBA + FPC = Possiblility???

**WILL** · 08-12-2004, 02:13 AM

I thought Free Pascal did this already...?

**Legolas** · 08-12-2004, 12:33 PM

Uhm... I don't think so. FPC crosscompiler currently does not compile code for gba. There is a version that can crosscompile from i386-linux to arm-linux, not to arm-elf.

**WILL** · 09-12-2004, 01:29 AM

Originally Posted by Legolas

Anyway I downloaded some documentation and sources... I think I'll try to make it, waiting for a freepascal crosscompiler. :rambo:

My response to this was that it already cross-compiles.

At the least it is what I had meant.

As for the GBA port of FPC, why not contact Noeska and FPK(easier to reach on IRC at #fpc, check the FPC website for the server) and see what may help? Noeska is good for it and FPK is willing under the right conditions...

I think what FPK is getting at is not only does he want to see it actually being used, unlike his other BeOS and Solaris ports, but that someone will actually be required to maintain it and handle bug reports and the like aswell.

However I think that we have already established that there is a want and some will use it. I certanly will if it's available to me. But is a handfull of people enough? Maybe, maybe not... I'll definately be looking into this further.

**Legolas** · 09-12-2004, 03:22 PM

Because of my little knowledge, I could only do some beta testing.

ops:
Maybe I can try to port some GBA C code (like libraries and so on) to Pascal.
If Noeska and FPC want a beta-tester, I'm here

**WILL** · 31-12-2004, 06:41 PM

Was there any further progress with this? Did FPK ever add it to the 'to do' list?

I'll see if I can search out some more information on this later on...

**Legolas** · 01-01-2005, 12:16 PM

I don't know about freepascal, but with a bit of headache and a lot of attempts I built a gpc cross compiler from cygwin to arm-elf that (theorically) could compile gba code

At this time I'm trying to convert some simple code from c to pascal to do some testing... Stay tuned!

**savage** · 01-01-2005, 05:49 PM

I think most of us are all ears!!!! Or should that be eyes?

Anonymous · 05-01-2005, 04:31 PM

[quote="noeska"]I think al that is needed on how to modify free pascal for the gba is written here: http://linux.gbadev.org/gcc-gba/ .

The important part is crt0.s as this defines the gba (cartridge/executable) header. But even more improtant is the lnkscript that is used. As that glues together the crt0.o with your applicton .o file in a special way. Without that ]

im pretty sure the gba supports both thumb and arm instruction sets

iirc due to bus issues thumb is faster when running from cart but arm is faster when running from ram.

**Legolas** · 05-01-2005, 04:59 PM

I can confirm that the gba cpu (arm7tdmi) can handle arm and thumb instructions set. AFAIK gcc for arm can switch between arm and thumb also, by compiling with -mthumb-interwork directive.

Anonymous · 05-01-2005, 09:35 PM

Originally Posted by Legolas

Uhm... I don't think so. FPC crosscompiler currently does not compile code for gba. There is a version that can crosscompile from i386-linux to arm-linux, not to arm-elf.

If I understood FPK ok, there is one main problem compiler side:

- FPC supports ARM, but only normal 32-bit ARM assembler. ARM also has a shortened 16-bit THUMB chipset. (not every ARM chip has this, it is an added option). FPC doesn't support THUMB instruction generation yet.

Besides that, the typical other tasks that must be done for a new port:
- somehow create startup code (the already mentioned crt0.[o|as])
- Create something that can interface with the OS.
- Interface to other compiler's libraries (typical GCC) to get access to code.
- Do stuff that is special for that port. (e.g. for Windows: DLL support)