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Hardware > burning my own eeprom

#26121 - nrpil - Wed Sep 08, 2004 9:43 am

Hello people,

I'm trying to burn my own eeprom, i read all kinds of things about the header of the file i'm going to use. The gba rom header seems to be different and doesn't work.

Can someone help me a little bit ?

I'm using:

- devkitarm gcc compiler
- 27c256 eeprom

Thanks,
Norbert

#26127 - FluBBa - Wed Sep 08, 2004 12:32 pm

It sounds like we have 2 problems here, try to resolve one at a time.
Can you run your program in an emulator (with BIOS so that it checks the header) or have you tried to burn something that is known to work on a real GBA?
_________________
I probably suck, my not is a programmer.

#26148 - nrpil - Wed Sep 08, 2004 3:06 pm

Hello FluBBa,

FluBBa wrote:
It sounds like we have 2 problems here, try to resolve one at a time.
Can you run your program in an emulator (with BIOS so that it checks the header) or have you tried to burn something that is known to work on a real GBA?


I've first used the gbdk, they use a different crt0 file for creating a <filename>.bin This <filename>.bin cannot be run in the emulator (visualboyadvanced) but can be burned into a eeprom. I'm now using the devkitarm which produced a <filename>.gba which can be loaded in the emulator but not in the eeprom.

I've seen the header fix programs but i think the crt0 from the devkitarm is not usable for burning into a eeprom.

Greetings,
Norbert.

#26157 - FluBBa - Wed Sep 08, 2004 6:01 pm

the filename extension should be no problem in VBA, if you have a program that runs in VBA rename it to filename.bin if your burner program doesn't like filename.gba
_________________
I probably suck, my not is a programmer.

#26182 - nrpil - Wed Sep 08, 2004 11:25 pm

i know the extensions are not a problem but it seems i cannot use a gba rom file to burn in a eeprom and run.

the layout from http://cvs.sourceforge.net/viewcvs.py/gbdk/gbdk-lib/libc/gb/crt0.s?rev=1.13&view=markup and devkitarm/arm-elf/lib/gba_crt0.s (in http://prdownloads.sourceforge.net/devkitpro/devkitARM_r8-linux.tar.bz2?download) differ. Is there a crt0.s for devkitarm which i can use to burn (and run) in a eeprom ?

Thanks,
Norbert.

#26252 - nrpil - Fri Sep 10, 2004 8:38 am

I guess i'm doiing something completely wrong, can anyone give me some pointer where to search ?

Thanks,
Norbert.

#26271 - phonymike - Sat Sep 11, 2004 12:00 am

we need some more information. you say that the .bin can be burned to eeprom, but the gba can't. are you saying that the output .bin will work in a gba when burned to an eeprom? it might be that your burning software only recognizes .bin files, and it won't flash a .gba file, in that case, rename the .gba to .bin.

if the file doesn't run in an emulator, then 99.99% chance it won't run on a gba. you need to take things 1 at a time. I think your problem is your eeprom:

as far as I know, the gba doesn't use pins connected directly to the eeprom to the cart bus. it needs some very simple logic to be in between. it's not like mono gb, snes, or genesis. if you want to burn an eeprom, then download an already working rom and burn it. open up a downloaded rom (there's plenty of demos on this site,) open it with visual boy advance emulator and under the file menu, click rom information. look at the bottom of the window that opened, it'll say CRC 18 (18) or whatever number and those should match. if they don't match, get another demo because the header isn't right. once you find a good one, flash that, and see if your eeprom even works.

if you can flash an already made demo to your eeprom, then your eeprom is okay, and you have to work on getting the right header for your rom. there's a program called gbarm which will add the nintendo logo data and fix the CRC, it's command line, so use it with the right switches. then your rom will work.