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crazyjul

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Posts posted by crazyjul

    Tiles problems clues

    in DS Emulators [/pc/ds]

    Posted

    Hi all,

     

    after some research, I've found that the register REG_WRAMCNT is set to 3 at startup.

     

    This means that video BANK1 and BANK0 are assigned to the arm7.

    But in that case, does the video system work as for GBA??

     

    Does anybody has idea about this???

     

    Crazyjul

    Work in progress

    in DS Emulators [/pc/ds]

    Posted · Edited by crazyjul

    VRAMmap is initialized in MMUMaininit in dsmmumain.c. It is initialized to nulls and then modified by writes to the VRAM registers. This is a recent change to get memory mapping working correctly (from 0.4.6). If you look at the MMUMainremapVRAM_BANK_A, etc functions you'll see where the initialization is done. Not all of it is implemented as I'm unsure how things like extended palletes, image textures, etc work.

     

    I have noticed some demos don't map the VRAM by writing to the registers. I wrote a simple test of this and when writing to the memory area (VRAM_A for example), the write appears to work but when you read the value back you get 0x00, not what you wrote. So I assumed that there is no default mapping.

     

    This may not be the case for sprites, or may not be the general case and only happened to be the case for the one that I tested of course.

     

    Prior to me doing the VRAM mapping code sprites did not work correctly either so there may be something more fundamental wrong.

     

    So I'll try to make a lot of test. I'll start from scratch. From what I've understood, there are default value in vram mapping register, when I'll get my flasher, I'll try to read them. I will also do some test.

     

    For the demo that does not work when not intializing the vram, they seem to write sprite at 0x06004000. On DsTekWiki, this is shown as Sprte memory, maybe when no memory is map to this address space.

     

    Crazyjul

    Work in progress

    in DS Emulators [/pc/ds]

    Posted · Edited by crazyjul

    I've looked at sprite code.

     

    It seems that VRAMmap is never initialized, so when the program writes data int othe vmemory, as the vram pointer is null, the write is just skipped.

     

    It seems that video memory remapping register is never written. Nobody knows any default value of it?? It maybe explained why some demo works (in fact, if they remap VRAM, it should work)

     

    I will have a look at this tonight.

     

    Crazyjul

    Work in progress

    in DS Emulators [/pc/ds]

    Posted · Edited by crazyjul

    The integer square root do not exist in C or C++ library. My first idea was to convert it to double, do the square root ad convert it back. but the conversion of a int64 to double can cause loss of data.

     

    For now, i'm using this solution, knowing that it's both inaccurate and slow to execute.

     

    I've made small test apps with libnds that just display the result of some division and square root. I'm just waiting my flash linker to validate the result of the emulator.

     

    //EDIT : I've send a patch to doublec

    Work in progress

    in DS Emulators [/pc/ds]

    Posted

    FIFO support is completed and added to the darcs repository. There are a few bugs I want to try and stamp out and then 0.4.7 will be released. Some of the E3 demos run further now, but it looks like the hardware divide and squareroot registers may need to be implemented to get them further along. I tested a couple of GBA demo's with the recently re-added GBA support and they worked fine.

     

    If you're interested in, I caan look at the square root and divider accelerator

    I've already had a look at it, I just need to figure somthing out, and I think it'll be complete

    Can't compile code from repository

    in DS Emulators [/pc/ds]

    Posted

    That would be great, thanks! The sram patch was a contribution I received and I applied the patch, but after I tested it I forgot to save and record the project.

     

    With the sram fixed, I've made a bit of cleaning.

     

    I've remove nearly all warnings.

    I also fix declarations of all function.

     

    I think I've found a bug:

     

    In the sqrt intruction, you're doing : src=arm7reg.r[0]; arm7reg.r[0]= (u32) sqrt(src);

     

    As far as I know, this sqrt is made on integer and not float. Am I right??

    If yes, as math.h was not include, sqrt was returning a float, but was treated as an int. IF no, the code should work,but it's better to cast the register as a float before calling sqrt.

     

    Hope it help

     

    I've send you the patchs with darcs send command.

     

    Crazyjul

    Can't compile code from repository

    in DS Emulators [/pc/ds]

    Posted

    To complete, when I compile the DS dll I get those link errors :

     

     

    dsmmumain.obj : error LNK2019: unresolved external symbol _sram_read referenced in function _MMUMainrdB

    dsmmusub.obj : error LNK2001: unresolved external symbol _sram_read

    dsmmumain.obj : error LNK2019: unresolved external symbol _sram_write referenced in function _MMUMainwrB

    dsmmusub.obj : error LNK2001: unresolved external symbol _sram_write

    glds.obj : error LNK2001: unresolved external symbol _sram_save

    glds.obj : error LNK2001: unresolved external symbol _sram_load

    .\..\..\Build\Debug/ds.dll : fatal error LNK1120: 4 unresolved externals

     

    Hope it help

     

    crazyjul

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