ROM Hacks/Edits .. without burning a ROM?

C_Ux2

Hello all,



As an artist I've done (and am working on) a host of different game related projects and always head over here for help when I get stuck.



I wonder if once again someone here might be able to help me.



I am currently working on a piece about landscapes in games and wanted to look at Mario on the NES. Whilst the first level and graphics for Mario are very iconic, I am hoping to look at what happens and how people react when these simple landscape features are broken and/or abstracted.



I am wondering then whether it is possible to 'damage' the chip / board in any way without removing it and wiping/burning a new chip so that the graphics will be distorted or play in weird ways?



I could of course start hammering away at things but I wonder if anyone has done something (perhaps accidently) in the past and seen the results on-screen first hand. The kind of thing i'm talking about is similar to what happens when the pins don't quite meet and you would blow on the cart to make it work.



Thank you! 

C_Ux2

riskVSreward

You could try clipping one of the legs on the rom. That could result in a bunch of things... garbled graphics being one of many possibilities.



Or sever one of the contact pins with an exacto.

removed04092017

You could pulse the pins with bad voltages and burn the transistors. Only hard thing would be making sure you don't destroy the entire chip, haha.

Lincoln

Yeah, it's actually pretty easy to just destroy the graphics, and you have a couple options:



1. destroy some address lines to the CHR chip. this is going to give you "wrong" graphics on the screen, as the data returned will be from a different part of memory than the game is expecting. I would start by cutting 1 line and see what you get for results. For each cut you make you are limiting the accessible area of the CHR chip, so I would think if you make too many cuts things are going to start to look uniform as you ended up returning the same wrong data more often.



2. destroy data lines from the CHR chip. I'm not sure of the results here but I think you are going to get more "corrupted" graphics, as the chip is trying to return the correct byte, but it's not going to be received correctly by the system. More cuts may enhance the effect with this approach.



3. completely cut power to the CHR chip by clipping pin 28. this completely disables the graphics data, and the system just ends up with garbage to display. But it's pretty consistent garbage, and you should still be able to play the game.



(this was all written in the context of SMB1)

C_Ux2

Thank you all, it's very much appreciated! I'll try some things out and see what works

Mario's Right Nut

I actually did Lincoln's #3 when I was making carts for my games. I missed programming a CHR chip a couple times and when I tested it, it was like Slappin' Atari Bitches. i.e. just blocks chasing each other around. The colors were still fine and everything else worked, it was just 8x8 blocks! Pretty awesome.

C_Ux2

Originally posted by: Lincoln



Yeah, it's actually pretty easy to just destroy the graphics, and you have a couple options:



1. destroy some address lines to the CHR chip. this is going to give you "wrong" graphics on the screen, as the data returned will be from a different part of memory than the game is expecting. I would start by cutting 1 line and see what you get for results. For each cut you make you are limiting the accessible area of the CHR chip, so I would think if you make too many cuts things are going to start to look uniform as you ended up returning the same wrong data more often.



2. destroy data lines from the CHR chip. I'm not sure of the results here but I think you are going to get more "corrupted" graphics, as the chip is trying to return the correct byte, but it's not going to be received correctly by the system. More cuts may enhance the effect with this approach.



3. completely cut power to the CHR chip by clipping pin 28. this completely disables the graphics data, and the system just ends up with garbage to display. But it's pretty consistent garbage, and you should still be able to play the game.



(this was all written in the context of SMB1)

Hello - quick update  



1 & 2 I couldn't seem to make work - either I am doing it wrong (which is likely) or I simply don't know what i'm doing (which is likely). Whatever I tried for 1 & 2 I would just get the grey screen of death.



Number 3 worked like a charm though, I got as you described: relative garbage but still playable. 

Guntz

The easiest way to corrupt graphics on an NES is to purposefully dirty up a game, or find an already dirty game. Only clean the PRG side of the edge connector, leave the CHR all dirty.

C_Ux2

I'm running out of SMB carts to experiment!



Does anyone know of any particular over-the-counter chemical that might corrode/damage the connectors?



[Edit: Hmm, thinking about it - might I damage the actual NES using chemicals on the cart? I might just stick to scratching things and damaging lines ]

Guntz

Try using a Game Genie instead and experiment with the CHR banks. Damaging the cartridge is really limited by comparison.

C_Ux2

I did consider this but the core of the project is in effect what happens when the hardware is damaged and how that is represented on screen, though if I get better results we could perhaps change this to when it's manipulated.