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hey,
i did a few searches and didnt turn up much.
can someone point me in the right direction?

all im looking to do is replace a few sound samples in a classic gb rom.

i know *some* asm, and im pretty confidant with hex / hex editors

thanx!

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New York City

I suppose it all depends on the ROM? It's not like data is stored at the same place in every software.
You will have to disassemble that thing, which I don't think is easy or pretty. But knowing the exact location of sound data won't be easy.

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true,
but i expect it to be stored in a similar way.
and the down and dirty process of replacement,
no matter where the data is... is what im looking for.

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New York City

This is a wild guess but, I don't think the samples would be stored in any sort of compressed way (just 4-bit linear PCM data), so you can try and load the ROM in a DAW or sound editor as RAW DATA and see where the samples are. You can get an approximate location offset that you can late peek at with your hex editor.
(just a whack idea, this is the shit i used to do with my Amiga, i never learned asm tongue)
Maybe that made sense?

A pro would disassemble the code and data, then recompile the whole thing again.

Last edited by akira^8GB (Feb 9, 2010 10:54 pm)

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*sigh*
i have tried a similarly asinine technique already with little results...
i was hoping someone had done something like this already and
had some kind of real situational knowledge. 

i'll just say it now,
im trying to change the samples in pounder.

akira^8GB wrote:

A pro would disassemble the code and data, then recompile the whole thing again.

god i wish i was pro
;D

Last edited by xero (Feb 10, 2010 1:58 am)

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New York City
xero wrote:

god i wish i was pro
;D

Same here bro,but going at it BRUTE style is both entertaining and also educational big_smile
Someone might be able to know how to do this, just wait for a more knowledgeable voice to chip in. But as LSDJ can be hacked with a simple JAVA software, probably this one too. As you think, you just need to know the format and where are the samples. Without that info it might be impossible. Have you tried contacting 8cylinder?

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Sweeeeeeden

I might have a look at this. As far as I remember from looking at Pounder a few years, the sound format is indeed 4 bits, just like in LSDj. Sample rate, I don't know/remember. If I were you though I would try to rewrite the program in asm. Actually that's what I did back then and failed for some reason. Maybe I should try again now...?
In the meanwhile, post the samples you want to use.

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nitro2k01 wrote:

If I were you though I would try to rewrite the program in asm. Actually that's what I did back then and failed for some reason. Maybe I should try again now...?
In the meanwhile, post the samples you want to use.

yeah,
ill hit yew up on gmail about this.

also i got an email from 8cylinder last night.
he said the version of the pounder rom on his site
is in fact not the newest version. he promised to
update the site soon.

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ad-hell-aide

In terms of Pounder - here are my guesses as to sample positions in the ROM file, with lengths and byte offets:
0 - 468 @ 16400
1 - 468 @ 32784
2 - 468 @ 49168
3 - 468 @ 65552
4 - 468 @ 81936
5 - 468 @ 98320
6 - 468 @ 114704
7 - (blank?)
8 - 469 @ 147472
9 - 471 @ 163856
10 - 469 @ 180240
11 - 468 @ 196624
12 - 540 @ 213008
13 - 470 @ 229392
14 - 468 @ 245776
15 - 540 @ 262160
16 - 1124 @ 278544
17 - 569 @ 294928
18 - (blank?)
19 - 89 @ 327696
20 - 49 @ 344080
21 - 534 @ 360464
22 - 900 @ 376848
23 - 613 @ 393232

Could be totally wrong, but replacing the first one at least seems to work...

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ad-hell-aide
nitro2k01 wrote:

I might have a look at this. As far as I remember from looking at Pounder a few years, the sound format is indeed 4 bits, just like in LSDj. Sample rate, I don't know/remember. If I were you though I would try to rewrite the program in asm. Actually that's what I did back then and failed for some reason. Maybe I should try again now...?
In the meanwhile, post the samples you want to use.


Do you think that the data is stored nibble-by-nibble?

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ad-hell-aide

The Gameboy program Pounder by 8cylinder lets the user trigger drum samples using the buttons and the directional pad. By hacking and replacing certain sections of the Gameboy ROM file, it is easy to replace the samples that are triggered. The aim of this post is to get you started - there are few different ways of going about replacing the sample data inside of the ROM.

Read more: http://little-scale.blogspot.com/2010/0 … under.html

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Miami

Very cool!

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Chicago IL

the samples you add have to be the same size as the ones youre replacing, right?

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ad-hell-aide

That is correct.

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☺☺☺

Ive developed a method based moreso on burnkit2600s approach. So far it works in GB and GBA roms . but then again burnkits approach is just littlescales without the fancy MAX patch smile

cough coughpocketmusic with custom samples cough coughc ough ghettopig track what cough cough

Last edited by Emar (Mar 15, 2010 2:11 pm)

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thanx little scale!