# Sega Saturn Swap Trick



## VashTS (Jan 21, 2014)

Hey all
I recently got my first Saturn! I've been messing with the swap method...for some reason they don't function as I would expect. 

I can get some games to load (Street Fighter The Movie, Mortal Kombat II, NBA Jam Extreme) but they freeze abruptly. Sonic 3D Blast is the most successful, it will get to in game but no BGM just sound fx. 

I've tried using different retail games to start the process with no change. 

I'm using the 1x swap method where you boot with a retail game -> reset at black screen with sega logo -> swap retail for backup at Saturn logo. 

Its a model 2 with round buttons. I got some pretty sweet games but of course I like to tinker and some of these games may not last much longer. 

I may just buy a mod chip but I don't really want to shell out $30. Anyone got any tips?


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## Foxi4 (Jan 21, 2014)

I nailed the swaptrick to down to a fine art, I think I'll be able to help you out.

The reason why your trick is not working is that when you reboot the system that way, it will still remember the ToC _(Table of Contents)_ of the Saturn disc you previously inserted, meaning that it will look for files according to the information index from the retail disc. This works with some games that share a similar ToC but freezes others! Normally you're supposed to start the process with the backup and allow the system to read the first trace so that you have the correct ToC in memory!

*Here's my tips and tricks:*

There are three _(basic) _ways of performing the swap trick and each has different benefits:
Boot with the copy disc in, wait for the lens to read the first trace, swap discs, wait for the system to read the security ring, swap discs. This way, the system reads the correct Table of Contents, then reads the Security Ring to assert that the disc is genuine and finally moves on to game data. This will work with the great majority of games.
Boot a retail disc, reset and swap, meaning the method you're using. This will keep the retail Table of Contents in-memory and may cause glitching, subject to game compatibility.
Boot with the backup disc in, wait for the console to load the whole disc and fail to boot, reboot, swap for a retail disc during the Security Ring read, then back to the backup. This helps when the ToC is poorly-burned or hard to read.

There are two Sega Saturn System Discs available online - the KD01 and KD02, first being for SEGA-branded games, latter for third-party ones. Now, what these discs do is that they disable the Sega Saturn's Security Ring mechanism. If you boot those discs with a swap trick, you should be taken to a black screen saying _"COMPLETE"_, this means that the Ring has now been saved in the console's memory and subsequent reboots _will not require you to swap at all_. It doesn't work with all games, but it does nullify compatibility issues with some that read the Security Ring more than once or during loading! Those two are _essential_ items!
I hope I was helpful. If you'll need additional pointers, I can post more tomorrow, I just have to hook up my Saturn.


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## XiTaU (Jan 21, 2014)

i have a model 1 saturn so i find the trick easy i have never tried with a model 2 but without the red light it is probably abit harder

i always put in backup wait for the light swap to retail reboot at saturn screen then after reboot wait for the light then swap to backup again
i dont even know how this process works without the light but im sure if u just learn the timings it will be simple enough.


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## Foxi4 (Jan 21, 2014)

It's less a matter of timing and more a matter of auditory prowess. Timing may differ depending on the medium the disc was burnt on, the state of the laser and other factors while the actual reads as well as the movement of the lens will always be audible. As long as you listen to what's going on, you should be just fine, with or without the light. 

The process is very simple - Read the Table of Contents -> Go to the pre-set Security Ring position and perform disc verification -> Check the Table of Contents, read the Game Data and boot the Binary.

Because the references to data are all in the Table of Contents, it's vital to have the correct one in-memory. The boot point of binaries is always the same, but audio tracks and other data rarely matches positions, so you will very likely experience glitches.

I remember that there was also one method of a quad-swap that sort-of bruteforced really bitchy things to work, but I can't quite recall what it was. I'll post it if it crosses my mind, I don't think I had to use it very often - only when the games were really terribly burned.

*Remember*, just because the game doesn't work doesn't mean that you're doing something wrong. Sometimes the discs you burn your stuff on... are... just... terrible for this purpose. The Sega Saturn CD lens is very picky, mine often turns its nose up at me when I try to feed it Tesco-branded CD's - she loves her high-end ones though.


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## VashTS (Jan 21, 2014)

i had a feeling is TOC related. im almost positive it is now. 

the single swap method is flawed i guess. time to start training for double swap.


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## VashTS (Jan 21, 2014)

i gave the double swap a try and sure enough the games play fine. 

start with backup in (reads TOC) -> swap to retail when security check -> swap back to copy when data is read


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## Foxi4 (Jan 21, 2014)

VashTS said:


> i gave the double swap a try and sure enough the games play fine.
> 
> start with backup in (reads TOC) -> swap to retail when security check -> swap back to copy when data is read


Fantastic! I'm glad that everything works now. 

If you'll run into any particularly _"difficult"_ games, do post.


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## VashTS (Jan 21, 2014)

Foxi4 said:


> Fantastic! I'm glad that everything works now.
> 
> If you'll run into any particularly _"difficult"_ games, do post.


 

NBA Jam extreme still failed on me, I might try to reburn it and see what happens.


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## Foxi4 (Jan 21, 2014)

VashTS said:


> NBA Jam extreme still failed on me, I might try to reburn it and see what happens.


There are several games that use an altered security scheme, NBA Jam might be one of them. Attempt a _"quad swap"_ trick:

Start with the backup, as usual, let the system read the ToC
Swap to a retail disc for the Security Ring verification
Swap to the backup, let it read boot data
Swap to a retail disc for a secondary check right after the logo disappears
Swap to the backup again
If this works, it means NBA Jam, much like NBA Action '98, is one of the troublesome games. You could try to combat the problem by burning a KD02 disc or a KD01 disc and modifying it to be compatible with third-party using Sega Region Patcher.


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## VashTS (Jan 22, 2014)

Foxi4 said:


> There are several games that use an altered security scheme, NBA Jam might be one of them. Attempt a _"quad swap"_ trick:
> 
> Start with the backup, as usual, let the system read the ToC
> Swap to a retail disc for the Security Ring verification
> ...


 
I started reading about this KD01 / KD02 disc, but it seemed cryptic. From what I gathered, if you get the system to read the KD disc you can then swap it for any game without worrying about the security check again. I was reading on isozone and some dude mentioned cutting a disc and I tapped out at that point.


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## Foxi4 (Jan 22, 2014)

VashTS said:


> I started reading about this KD01 / KD02 disc, but it seemed cryptic. From what I gathered, if you get the system to read the KD disc you can then swap it for any game without worrying about the security check again. I was reading on isozone and some dude mentioned cutting a disc and I tapped out at that point.


No, no, no - you don't need to cut any discs at all. The mod he's referring to is _"The Rings of Saturn"_ which is a highly-experimental DIY solution. Essentially you burn a disc, cut it down to a MiniCD format, take a retail game, cut a MiniCD hole in it and stick the two pieces together. Naturally this can make the motor go off-balance if you cut it/stick it/weigh it wrong and cause all sorts of monstrous issues - I personally don't recommend it unless you have the right tools to cut out a perfect circle and don't mind sacrificing a disc to extract the Security Ring.

KD01 and KD02 just have to be burned, you boot them as you would boot a normal Saturn game using the swap trick. Once the system prints out the "COMPLETE" message, you swap out for a backup copy and press the reset switch - from now on until you power down, the Security Ring check should be completely disabled. Unfortunately, this isn't compatible with all Saturn games due to the nature of the swap trick - the system doesn't know that you've switched discs so it doesn't read the new ToC. This is why it's handy to have an external switch for the drive lid to flip at will.

*EDIT:* I just realized that perhaps there may be a way for it to work perfectly fine with the backup's ToC in-memory if you perform the reset swap:

Backup copy full read until failure
Swap for a KD disc
Reboot
Read KD disc with swapping at the security check
Swap for backup and reboot
The binary of the KD disc should start at the same point and there are no extra assets, so technically it shouldn't glitch out and at the same time, it should disable the security check. Something I'll have to test myself in my spare time, it just occured to me.


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