Trimmed roms with the R4

[burns11]

I know what trimming does and all, but are there any negatives (either across the board or with specific games)?

Also, is one rom trimmer better than another?

[{{909}}]

ive trimmed every game thats on my 2gig card and every one works, thats using the official trimmer off the R4 website.

[aerowinged]

I was just going to start a new thread, but it seems to be on topic with this one.

Could someone explain what trimming roms actually does and why? in newb terms.

And is it something i should be doing to every rom?

[revnull]

Let me preface this with "From what I understand". Commercial NDS carts have fixed storage sizes (8MB, 16MB, 32MB, 64MB, 128MB).

Example 1: If the "actual" size of the game/rom is 14MB, it is manufactured on a 16MB cart.
Example 2: If the "actual" size of the game/rom is 70MB, it is manufactured on a 128MB cart.

When a rom is dumped, the software dumps the entire cart, not just the game content but the "empty space" as well. In example 1, after dumping, you will have a 16MB rom file. Running this rom through a trimming program removes the extra "empty space" from the rom file. The rom in example 1 should trim down to 14MB of game content. Trimming the rom from example 2 will give you a 70MB rom file. Trimming your roms will free valuable space on your R4/M3 memory card allowing you to fit more games.
Please keep in mind, not all trimmers are created equal. I personally have had trimmed roms (2 so far) not load or freeze in the middle of the game. For the games I have had problems with, I just load the untrimmed rom and it works fine.

[mogs]

what is the best program to trim roms?

[ShoFly]

I started using this. Much better.
http://gbatemp.net/index.php?showtopic=43576