ROM decompression and offset tables

[modman]

helo

 

ive been working on an npc edit for quite some time now, and id like a little explanation on the following topics:

 

1. is it a smart idea to decompress your rom ANY TIME you do an edit, or is it best to save that step for specific edits?

2. someone mentioned the reason i was running into cpu errors last time is because i never updated zeldas filesystem with my edit. how can i go about updating these tables?

 

heres a rundown of the r4300i error i was getting last time i worked on this:

http://forums.zelda64.net/topic/11331659/1/

[modman]

mzxrules mentioned some helpful hints in my zelda64 thread:

 

1) no, because that sounds incredibly stupid. You want to decompress the rom ONCE, and then keep copies of that decompressed rom. If you're editing the Ocarina of Time Debug Rom, you don't even have to do that.

2) http://wiki.cloudmodding.com/oot/Filesystemgives a rundown of the structure, http://wiki.cloudmodding.com/oot/File_List_(Debug) lists what files are being referenced in the file table. Basically, if you add more data to the end of a file, you need to go back and change the size of the file in the file table so that it's big enough to load the new data.

 

Probably not actually an issue, but note that all the files in the table have an end address that ends in a 0. This is because the end address is aligned to the nearest 0x10 byte. So if the real end address ends with something like 0x...9532, you'd set an end address in the file table as being 0x...9540.

 

Oh also, any time you modify the file table data, you will need to update the rom's CRC. There are programs that will do it, but I don't know the best one.