Help with Swapping out New Title Screens for Old

[pixelgrind]

Hello one and all,

 

I'm new to the forums, new to pixel art, new to the idea of hacking ROMS.

here are some sketchy examples, just wanta customize some coleco ROMS.

 

once I get Tony Cruises' MSX/Coleco Sprite/Tile Maker back up and running(issues opening latest)

at least then Ill be able to cut and paste the code somewhere.

the trick is:

A) knowing how to open said ROMS/Program to use (text editor?)

B) knowing where to paste new tile data.

C) is that how it is even done?

 

any advice greatly appreciated.

 

Cheers + \m/ \m/

 

[youki]

You can not do what you want to do.

 

The games you want change the title screen don't use "custom title screen".  They use the standard title screen which is coded in the Colecovision ROM BIOS itself , not in the cartridge.

In the cartridge rom you will find only the Text.  "VENTURE" , "PEPPER II"  etc...   so the only thing you can change easly is if you want rename PEPPER II to PEPPER I for instance. But not put graphic title.

 

To do that, it is lot more complex, you have to dissamble the cartridge rom and Invert 2 bytes in the header in order the coleco do not display the default title screen and  implement code that load your own pattern , Name and Color Table   that you have also to include in your data section.   that's a developper work , not a simple cut and paste byte at the right place.

 

 

Edited May 26, 2021 by youki

[pixelgrind]

ahhh the BIOS I was wondering about that.

 

thanks for taking the time to answer my question....looks like back to the  drawing board for me.

 

cheers

[Tony Cruise]

5 hours ago, pixelgrind said:

Hello one and all,

 

I'm new to the forums, new to pixel art, new to the idea of hacking ROMS.

here are some sketchy examples, just wanta customize some coleco ROMS.

 

once I get Tony Cruises' MSX/Coleco Sprite/Tile Maker back up and running(issues opening latest)

at least then Ill be able to cut and paste the code somewhere.

the trick is:

A) knowing how to open said ROMS/Program to use (text editor?)

B) knowing where to paste new tile data.

C) is that how it is even done?

 

any advice greatly appreciated.

 

Cheers + \m/ \m/

 

If you are having problems installing the latest version of my Sprite and Tile Editor, make sure you uninstall any old versions first and then do a fresh install.  I switched from a 'Click Once' installation to a proper (offline) installation package.  It is also fully signed, but of course the rules are now changed and Windows 10 still puts up a warning.  I will have to replace the certificate with one with a higher level of encryption (and of course more cost).

[Tursi]

They are NICE looking screens... I think the main problem even for a coder will be finding enough free bytes in the ROM to fit them. For instance, Venture looks to have about 47 bytes free at the end of the ROM.

 

The lack of free space takes it from a mild challenge to a bigger one, since now you have to find optimization or compression opportunities. 

 

It's too bad, they are very nice looking 

 

 

 

[pixelgrind]

 

 

 

....alas pixel art limbo for the lot.

 

in any event, thanks for the kind words, I appreciate it.