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Author Topic: [HELP] Find ROM address of Attribute table and adding a sprite in X/Y pos. (NES)  (Read 1430 times)

ShadowOne333

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Hello community.

I am trying to change the attribute palette data of a particular sprite in one of my hacks.
As you can see, the Konami logo is the one I'm trying to change (Tile ID: D8, which has it's attribute palette data stored in the PPU Address $23CB.
The X/Y positions in the Name table viewer are X: 12 and Y: 06.

it has 8F by default, and I want to change it to BF as the picture shows so that the palette of the logo matches the original one.
I've been searching for a while but I cannot seem to find where the attribute table for that sprite is. :/

Spoiler:


Also, I want to add the three little spike-like sprites at the bottom-right corner of the PPU Viewer to the top and the bottom of the number "III", but I don't know how to add those to the title screen.
My guess is that finding the attribute table (YY TT AA XX) for those sprites should do the trick, so that modifying the YY and XX positions can make them appear there, but I could be wrong though.

If someone can help out with these two issues, please let me know!
« Last Edit: April 14, 2016, 04:18:36 pm by ShadowOne333 »

KingMike

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Scratchpad is not a file hosting service (at least not for normal purposes). Use imgur or something.
"My watch says 30 chickens" Google, 2018

ShadowOne333

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Scratchpad is not a file hosting service (at least not for normal purposes). Use imgur or something.
Fixed. Used Tinypic, sorry about that.

KingMike

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You know ASM? Set a write breakpoint for PPU $23CB and work backward.
Also, I'm not complete sure which object you're talking about, but if it's one the same tileset (the same left/right half of the PPU viewer) as the background tiles, then it is likely a background tile.
Have you verified if it's a sprite or a background tile by using the menu options (or hotkeys) in FCEUX to turn off the BG and sprite layers?
"My watch says 30 chickens" Google, 2018

ShadowOne333

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You know ASM? Set a write breakpoint for PPU $23CB and work backward.
Also, I'm not complete sure which object you're talking about, but if it's one the same tileset (the same left/right half of the PPU viewer) as the background tiles, then it is likely a background tile.
Have you verified if it's a sprite or a background tile by using the menu options (or hotkeys) in FCEUX to turn off the BG and sprite layers?
I'm not really familiar with ASM, but at least I understand the basics, though I don't know how to use the FCEUX's breakpoint system. :/
Would you mind helping me out with that?

And yeah, it isn't a sprite, but rather a Background tile since it's in the right portion of the PPU Viewer.
The only sprite in that screen is the cross, the rest is all background tiles, so everything I want to do is related to Background tiles.

EDIT:
Was I supposed to put the offset of the PPU in the left box?
I got this:
Code: [Select]
0F:EBDC:85 02     STA $0002 = #$40
 0F:EBDE:B1 00     LDA ($00),Y @ $EC64 = #$D0
 0F:EBE0:A4 02     LDY $0002 = #$40
>0F:EBE2:8D 07 20  STA $2007 = #$00