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passme

Started by fattybumbum, August 01, 2005, 10:56:50 AM

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fattybumbum

do we know why the passme won't run commercial NDS roms?

:!:

stupid2ass

Quote from: "fattybumbum"do we know why the passme won't run commercial NDS roms?

:!:
Not on its own it won't (you still need a linker).  
They just say it to cover their asses.

fattybumbum

i have got a flash linker, it will run the homebrew ones but I can't get it to run the commercial ones I have.

cory1492

the commercial roms are hard coded to load ingame data off the NDS slot. my understanding of this is that the code provides the NDS cart (using a register) a offset and data size, then the cart transmits the data to the program requesting it (encrypted data I might add).

For the DS roms to work on a gba cart (neoflash/gst did this with their cart and "special" roms) the ROM needs to be hacked so that instead of the running application providing a register value with offset and size, it uses the offset and size to memcopy (software instead of hardware) the data (instead of relying on the ds cart to send it with hardware based memcopy). In the case of files over 256mbit, gba flash carts also need to have additional bankswitching instructions added to allow the data that is past 256mbit (the limit of the gba slot's addressing) to be relocated to be addressable.

a little technical, but it makes sense.

Essentially, the clean roms do run on the cart, but as soon as they go to access any data from the file system of the ROM, it tries to access it from the NDS slot instead (which is redirected by passme to the gba slot which does not have the registers like the DS slot does), resulting in the white screen instead of the intro screen (which would be stored in the file system instead of the binary that is running)

short story: it is not the passme/flashme/wifime's fault, it is the way the code is written ;)

fattybumbum