Hacking I am confused by all the ROMs and what to use

[Cyborg Ninja]

I have a ROM labeled R4i 3DS Revolution for DS with 3DS XL (LL) 3DS NDS XL (LL) NDSi NDSL NDS on the bottom. It's in gold lettering and a swirl design made out of dots on the right side. It looks like this:
http://www.r4ids.cn/images/r4igold3ds_1st_4.5_10_1.jpg
excluding whatever the right side of that image is saying about Revision C or whatever.

I have 3DS firmware update 9.9. I tried years ago to get an update for the ROM, but I would have had to use a system that was not updated in order to do it. I'm hoping things have changed by now. I have two 3DS systems and they are both 9.9. What can I do?

 

[Mikemk]

Mine works out of the box. You can always downgrade the 3DS.
Also, you have a flashcart, not a rom.

 

[The Catboy]

That little "C" there is actually the important part, depending on what's printed there will depend on how high you can update the R4i Gold's firmware (note the Wood R4 is a kernel, not a firmware.)
Since you are on 9.9 and it's not working. I suggest getting that system setup with a CFW instead. Current CFWs have TWL (DS/DSi) patches that allow any flashcart to work on the 3DS, so long as they worked on v1.0. As well there are now apps that will load flashcarts like the DSTT and R4 on the 3DS.
So my suggestion is to study this guide, so you know what you are getting into. Then using said guide to setting up a CFW.
Do not update your system past 9.9 until you are done hacking it! 11.4 can not be hacked!

 

[Cyborg Ninja]

You're right, it's a flashcart. My brain isn't quite pumping blood this morning. I'm not comfortable with downgrading the 3ds at the moment, but I'll think about it. BTW, my flashcart says Deep Labyrinth if that helps. I don't know what the "c" stands for. I do see the C now on my flashcart. What can I do besides downgrading the 3ds? It's been a few years, and I don't remember for sure how to install firmware to the flashcart properly, or at least I don't think I do.

 

[The Catboy]

You're right, it's a flashcart. My brain isn't quite pumping blood this morning. I'm not comfortable with downgrading the 3ds at the moment, but I'll think about it. BTW, my flashcart says Deep Labyrinth if that helps. I don't know what the "c" stands for. I do see the C now on my flashcart. What can I do besides downgrading the 3ds? It's been a few years, and I don't remember for sure how to install firmware to the flashcart properly, or at least I don't think I do.

Take your time, just keep your system as it is in case you change your mind. I can't force you, but I heavily suggest it.
So the little number/letter was basically the batch they belonged to and can determine just how far they can upgrade. This was mostly done so they could keep making/selling new carts. Now going to their site you see they list two different firmware updates, one for 6,7,8,9,A,C, which should actually work on 9.9 (don't quote me, this from memory.) Now if your's has a lowercase "c", then it's one of the carts build before DSi 1.4.5. Which was basically around the time 3DS OFW 6.0 came out and Nintendo basically gave up on DS flashcarts as whole.
Basically your's would be too old to update to the latest firmware provided by the R4i Gold team. Mine is version c as well and I had to install a CFW to get it to work on my 3DS.

 

[Cyborg Ninja]

Thanks Crystal. Now let's say it's an uppercase C, does that mean I can upgrade the firmware? What firmware do I download and install exactly? There are so many different ones that I'm confused, and this one is pretty old like you say.