This is, admittedly, getting into dicey territory, but I'm wondering if there is any kind of ASM (or other) framework out there for assembling NES/Famicom multicarts as ROMs.
As in: a script or application or framework which could assemble many 40k NROM NES ROMs into a single ROM. Or alternately could assemble NES ROMs of varying sizes into a single ROM. Or alternately could assemble 2k or 4k Family BASIC minigame NES ROMs (which all use the same graphics) into a single ROM.
We all know those pirate multicarts which turn up as ROMs or as their own systems. Here's an example ...
https://bootleggames.fandom.com/wiki/Famicom_YarouFamicom Yarou 54 contains 54 games, mostly hacked versions (by Inventor) of early 40kb NES NROM games, and a few bootleg originals by Nice Code, which seem to be 64kb in their original form but also run off of two CHR graphics banks like a 40kb game. There is a bunch of empty CHR space in the ROM code.
The menu seems to just set which PRG and CHR banks are being used.
It is possible (and straightforward) to copy/paste the original ROM data, minus the header, into this multicart ROM, replacing their weird hacked versions of the games. The original games' PRG data appears in the first half of the ROM in various banks, and the CHR data appears toward the end somewhere in various banks.
Twinbee appears to be cut down to NROM size here.
Other multicarts use games of varying size, and even this one seems to do that to an extent.
Here's a "1280-in-1" multicart whose "524-in-1" section seems to include the elusive, undumped original Pikachu5 version of "Wonder Rabbit/Monster Brother."
https://www.youtube.com/watch?v=0QWX8AZDc8sIf I were making ROMhacks and original NES games, it would be at least interesting to combine several of them into one Multicart ROM. This could also be useful for combining several related minigames, which might not be as interesting on their own, into one coherent idea.
Such as, let's say, original minigames made in NESMaker.
Alternately: Recently, ozidual of Gaming Alexandria and others have been preserving games made in Famicom Family Basic back in the 80s and 90s. This was a keyboard/ programming add-on for the Famicom which allowed for 2k of programming RAM, or 4k in the 1985 V3 update. Programs for Family Basic were published in magazines at the time and on audiocassettes. These can, through a convoluted process (STTONES), be typed up and converted into standalone NES ROMs as minigames, in a standardized format.
These games all use the same graphics banks (unless hacked). The amount of code is only about 2k or 4k plus a background nametable. (Possibly two, although I've yet to see an example of that.) This is compiled from about 100 lines of code or less.
(Family Basic V2 was copied as GBASIC and FBASIC on the knockoff Subor and Dendy Famiclone computers, and most "educational" unlicensed multicarts included Family Basic in some form as the main attraction, such as Bravesoft Windows 2000.)
These games are not all that interesting as standalone releases but would work well as a multicart combining many examples of what Family Basic can do. In this case every game would use the same graphics, and much of what's in the ROM wouldn't be needed (theoretically) as it's the same each time.
I see this user has made his own multicart of various ROMhacks.
http://bootleg.games/BGC_Forum/index.php?topic=3046.msg21960#msg21960There's also this whole situation ....
https://clusterrr.com/coolgirl/https://github.com/ClusterM/coolboy-multirom-builderhttps://github.com/coolgirl-multicart/coolgirl-multirom-builderhttps://coolgirl.clusterrr.com/constructor/ I'll have to look into that.
Basically I'm looking for a framework which would make it easy to compile minigames or NES ROMs into a multicart, with a multi-page menu and title screen artwork.