Gameboy Development Forum

Exactly what causes the bug? Have you tried to pinpoint the problem?
You can probably boil it down to a certain statement that cuases the bug. Care to post some code?

dox wrote:

Check the other thread about C vs Asm.

I looked and there is no information in that thread about it.

nitro2k01 wrote:

Exactly what causes the bug? Have you tried to pinpoint the problem?
You can probably boil it down to a certain statement that cuases the bug. Care to post some code?

Yes, I've tried pinpointing it, but I always get strange results. Commenting out certain lines will fix it, but that's definately not an ideal solution.

Here is some similar stripped down code that has the same problem:

#include <gb\gb.h>

void init(void);

typedef struct tObj_
{
    UINT8 inUse;
    UINT8 offset;
}tObj;

typedef struct tGroup_
{
    UINT8 x, y;
    tObj objs[10];
}tGroup;
tGroup groups[8];

void main(void)
{
    init();
    
    for (;;)
        {wait_vbl_done();}
}

void init(void)
{
    UINT8 i, t;
    
    groups[0].x = 0;
    groups[1].y = 2; // comment out this line and it compiles fine O_o
    
    for (i=0; i!=8; i++)
    {
        for (t=0; t!=10; t++)
        {
            groups[i].objs[t].inUse = 0; // comment out this line and it compiles fine O_o
        }
    }
}

lcc's output is as follows:

lcc wrote:

main.c(33):error *** FATAL Compiler Internal Error in file 'gen.c' line number '349' : code generator internal error
Contact Author with source code

And then it crashes with the usual "sdcc.exe has encountered a problem and needs to close.  We are sorry for the inconvenience." error.

nitro2k01 wrote:

Just a wild, untested guess, but what if you put x and y on separate lines in the struct?

Doesn't work ):

www.BoumPower.ch wrote:

I use GBDK and I'm not efficient with C (I write a lot with Borland Delphi-Pascal)

I'm currently writing a GB simulator (not emulator) that can help for writing GBDK software.

The main philosophy is to just add some conditionnal defines in the code and compile with LCC-WIN32 that produce a dll. The dll is linked to the GB simulator and run like a cartridge (on Windows OS). The LCC-WIN32 will probably display better error messages. The simulator will also have powerful debug capabilities but some native Gameboy access or assembly code will not be supported (need to have different code for GB or simulator with conditionnal defines)

Oh cool! Things are starting to cook in the GB dev world! Joshua, a guy who's hanging on the #gbdev IRC channel is currently doing a project called FPGABoy (Not the same as Costis' project) which is aiming for a complete GB clone made using an FPGA (programmable logic)
I've seen the GB-PIC project long ago, but I thought it was dead. Is this project an extension of GP-PIC or something completely new?
One problem I can think of is that there's no way for the cartridge to interrupt the CPU. The closest you can come to that is to hook up something to the serial port and send a byte when you want to go into debug mode.
I think FPGABoy also has a good potential of becoming a nice debug board since you can theoretically single step the CPU and keep all register values and stuff in sync with the code running.
Hmm, now I got another idea too... What if you could have a piece of programmable logic inside a GB which controls the clock rate... That way you could single step the CPU by only sending a certain amount of clock pulses at any one time. You still couldn't set up conditional breakpoints based on (all) reads and writes.
Jaja! Rant mode over.

www.BoumPower.ch wrote:

<snip>

I'm afraid I have no idea what you are talking about (: I'm not very knowledgeable about these things (at all), but to me it sounds like a way to run and debug the same code on both the Gameboy and certain PIC microcontrollers or a way to debug code running on actual hardware.

I don't think I'll be using GBDK anymore anyways since I've become comfortable with RGBDS and the absolute control over the hardware it gives me. Though if it ever becomes stable in the future I might consider using it for writing simpler applications (which is problably all I'll ever write anyways XD).

Good luck with your project (:!