EverDrive Forum

General => FXPAK (SD2SNES) => Topic started by: leonquest on October 09, 2018, 04:03 PM

Title: Save states on SD2Snes
Post by: leonquest on October 09, 2018, 04:03 PM
Alright,  SmokeMonster hasn't posted this yet, so I will.

https://twitter.com/furious_/status/1049471954468696064?s=19
Title: Re: Save states on SD2Snes
Post by: hex12 on October 09, 2018, 07:06 PM
Savestates are available only for non-special chip games
Title: Re: Save states on SD2Snes
Post by: Greg2600 on October 09, 2018, 07:27 PM
OMG, this is awesome!  Even if it's not for the chip-games. (for now)
Title: Re: Save states on SD2Snes
Post by: OmenBoy on October 09, 2018, 08:48 PM
OMG, this is awesome!  Even if it's not for the chip-games. (for now)

Probably forever as this Save State implementation uses the FPGA, hence why special chip games are not supported.
Title: Re: Save states on SD2Snes
Post by: leonquest on October 09, 2018, 10:32 PM
Enjoy people enjoy!! no more grinding through Contra, just use save states!

No more losing your game saves, use states!

No more mastering games, become a lazy bastard and cheat!  ;)
Title: Re: Save states on SD2Snes
Post by: Gumball on October 10, 2018, 02:48 AM
Question does this firmware have the SA-1 and super fx support as well?
Title: Re: Save states on SD2Snes
Post by: leonquest on October 10, 2018, 03:57 AM
Question does this firmware have the SA-1 and super fx support as well?

No sir, tweet says so, no support for special chips. probably no space in the FPGA to do both things.
Title: Re: Save states on SD2Snes
Post by: GyaragaX on October 10, 2018, 05:07 AM
Question does this firmware have the SA-1 and super fx support as well?

No sir, tweet says so, no support for special chips. probably no space in the FPGA to do both things.

It doesn't support savestates for special chips, but it does run them. It has GSU and SA-1 cores in the package.
Title: Re: Save states on SD2Snes
Post by: Jurai on October 10, 2018, 06:02 AM
the music still playing after you load the state seems to have an interesting effect in Actraiser 1, reloaded a save state at the first boss right before the music switch for the boss fight and the boss music never started and the boss AI never went into action, just stood in place while i walked over and finished him off, can't say for sure this doesn't happen in regular emulator savestates but thought it was funny
Title: Re: Save states on SD2Snes
Post by: FURiOUS on October 10, 2018, 02:22 PM
the music still playing after you load the state seems to have an interesting effect in Actraiser 1, reloaded a save state at the first boss right before the music switch for the boss fight and the boss music never started and the boss AI never went into action, just stood in place while i walked over and finished him off, can't say for sure this doesn't happen in regular emulator savestates but thought it was funny

Emulators generates a full save state of everything, including APU, flashcarts savestates don't and I think that never will happen.
Some games can crash because, there's a file (savestate_fixes.yml) in the package with some fixes for games with audio issues, basically the game stores the state of the APU ($214x) somewhere in the memory and it needs to be updated right after the load/save state.

RedGuy made that fix list, but he won't work on this savestate stuff anymore. I'll try to fix some games but I'm not a expert debugging them...
Title: Re: Save states on SD2Snes
Post by: hex12 on October 10, 2018, 04:05 PM
New update.

https://twitter.com/furious_/status/1050002481420427265

"New update for sd2snes 1.8 firmware with built-in savestates!
Fixed a few bugs and added new features:
- Custom base input for state slot selection (default: select)
- Choose which controller will do save/load/slot functions"

Download (beta): https://t.co/XD97S98nOo
Title: Re: Save states on SD2Snes
Post by: OneBagTravel on October 10, 2018, 04:26 PM
What an amazing community of developers! Not that I'll ever use save states like a dirty cheater  ;), it's a feature I'm sure a lot are happy to see.
Title: Re: Save states on SD2Snes
Post by: OmenBoy on October 10, 2018, 06:49 PM
Question does this firmware have the SA-1 and super fx support as well?

No sir, tweet says so, no support for special chips. probably no space in the FPGA to do both things.

I think he was asking if this firmware still has the ability to play Super FX and SA-1 games, not if they support save states with those games. Yes this firmware supports playing special chip games like Super FX and SA-1.
Title: Re: Save states on SD2Snes
Post by: Jurai on October 11, 2018, 12:06 AM
the music still playing after you load the state seems to have an interesting effect in Actraiser 1, reloaded a save state at the first boss right before the music switch for the boss fight and the boss music never started and the boss AI never went into action, just stood in place while i walked over and finished him off, can't say for sure this doesn't happen in regular emulator savestates but thought it was funny

Emulators generates a full save state of everything, including APU, flashcarts savestates don't and I think that never will happen.
Some games can crash because, there's a file (savestate_fixes.yml) in the package with some fixes for games with audio issues, basically the game stores the state of the APU ($214x) somewhere in the memory and it needs to be updated right after the load/save state.

RedGuy made that fix list, but he won't work on this savestate stuff anymore. I'll try to fix some games but I'm not a expert debugging them...

yeah I might look into it if I find some time just thought it was funny seeing the boss just frozen in place til it died, does also cause some unwinnable scenarios if the boss starts off screen though, so be wary if saving before an Actraiser boss fight
Title: Re: Save states on SD2Snes
Post by: leonquest on October 11, 2018, 03:21 AM
the music still playing after you load the state seems to have an interesting effect in Actraiser 1, reloaded a save state at the first boss right before the music switch for the boss fight and the boss music never started and the boss AI never went into action, just stood in place while i walked over and finished him off, can't say for sure this doesn't happen in regular emulator savestates but thought it was funny

Emulators generates a full save state of everything, including APU, flashcarts savestates don't and I think that never will happen.
Some games can crash because, there's a file (savestate_fixes.yml) in the package with some fixes for games with audio issues, basically the game stores the state of the APU ($214x) somewhere in the memory and it needs to be updated right after the load/save state.

RedGuy made that fix list, but he won't work on this savestate stuff anymore. I'll try to fix some games but I'm not a expert debugging them...

Does that mean Redguy is the one who started the work on save states? he never ceases to impress us.
Title: Re: Save states on SD2Snes
Post by: Terminator2k2 on October 11, 2018, 11:58 AM
the music still playing after you load the state seems to have an interesting effect in Actraiser 1, reloaded a save state at the first boss right before the music switch for the boss fight and the boss music never started and the boss AI never went into action, just stood in place while i walked over and finished him off, can't say for sure this doesn't happen in regular emulator savestates but thought it was funny

Emulators generates a full save state of everything, including APU, flashcarts savestates don't and I think that never will happen.
Some games can crash because, there's a file (savestate_fixes.yml) in the package with some fixes for games with audio issues, basically the game stores the state of the APU ($214x) somewhere in the memory and it needs to be updated right after the load/save state.

RedGuy made that fix list, but he won't work on this savestate stuff anymore. I'll try to fix some games but I'm not a expert debugging them...

Does that mean Redguy is the one who started the work on save states? he never ceases to impress us.

yes redguy had his usb2snes firmware, and this is a port of that
Title: Re: Save states on SD2Snes
Post by: the_randomizer on October 13, 2018, 01:39 AM
Nice, that's pretty cool to see  ;D
Title: Re: Save states on SD2Snes
Post by: Torgod13 on October 13, 2018, 03:13 AM
Looks like this is not working with 8BITDO controllers..  Any one else tried it with the 8BITDO?
Title: Re: Save states on SD2Snes
Post by: Jurai on October 13, 2018, 05:17 AM
Looks like this is not working with 8BITDO controllers..  Any one else tried it with the 8BITDO?

Works for me on the SN30, though I do admittedly have to press one button then the other while held down, does not work vice versa, believe I had to hold start then press the save or load button (L/R)
Title: Re: Save states on SD2Snes
Post by: Dup84 on October 13, 2018, 06:43 PM
Using PS4 and Wii controller, work fine (via 8bitdo)
Title: Re: Save states on SD2Snes
Post by: galvatron1983 on October 17, 2018, 04:55 PM
FYI, the in game hook doesnt work with save states enabled.
Title: Re: Save states on SD2Snes
Post by: Torgod13 on October 17, 2018, 06:06 PM
Ok.. Got it to work..  The instructions are a bit janky.. Needed to use the shoulder buttons.
Thanks Jurai for the tip!!
Title: Re: Save states on SD2Snes
Post by: the_randomizer on October 18, 2018, 06:03 PM
not perfect beta

What do you expect a beta to be, perfect? Don't be so ungrateful and learn some respect.  ::)
Title: Re: Save states on SD2Snes
Post by: OmenBoy on October 18, 2018, 06:55 PM
not perfect beta

No, more like not perfect user.  ;)
Title: Re: Save states on SD2Snes
Post by: boozer on October 23, 2018, 03:36 PM
Noob question but downloading the package from the twitter link and also from Krikzz download page they appear to be different sizes and have additional files. Both are v1.8.

Is the Redboy one a parallel version?
Title: Re: Save states on SD2Snes
Post by: Kiprian on November 05, 2018, 07:56 AM
Looks like this is not working with 8BITDO controllers..  Any one else tried it with the 8BITDO?
How did you connect the joystick 8bit to the supernintendo? I have such a gamepad, can I connect it?

Can you please tell me how to calculate the button calculator, I do not understand?

Title: Re: Save states on SD2Snes
Post by: Kiprian on November 05, 2018, 10:58 AM
after turning on the save status, the hot keys stopped working.
Title: Re: Save states on SD2Snes
Post by: Relikk on November 06, 2018, 10:40 AM
after turning on the save status, the hot keys stopped working.

Somebody already mentioned this a few posts above you...

FYI, the in game hook doesnt work with save states enabled.


Looks like this is not working with 8BITDO controllers..  Any one else tried it with the 8BITDO?
How did you connect the joystick 8bit to the supernintendo? I have such a gamepad, can I connect it?

Can you please tell me how to calculate the button calculator, I do not understand?

I presume you need one of these...

https://shop.8bitdo.com/products/retro-receiver-for-snes
Title: Re: Save states on SD2Snes
Post by: Gumball on November 21, 2018, 06:09 PM
I know save states dont work with chip games but do SA1 and GSU games still work on this firmware?
Title: Re: Save states on SD2Snes
Post by: Kiprian on November 26, 2018, 03:06 PM
Please tell me how to calculate correctly on the gamepad buttons calculator? In the instructions I do not understand. thank you.
Title: Re: Save states on SD2Snes
Post by: Lomax on November 28, 2018, 06:58 AM
So is this feature going to find it's way into an "official" firmware at some point?
Title: Re: Save states on SD2Snes
Post by: Spoonman on December 31, 2018, 10:21 AM
So is this feature going to find it's way into an "official" firmware at some point?

Hope so.
Title: Re: Save states on SD2Snes
Post by: FeverDrive on January 10, 2019, 09:46 PM
So is this feature going to find it's way into an "official" firmware at some point?
It seems like it will according to this page. (https://sd2snes.de/blog/status)
Title: Re: Save states on SD2Snes
Post by: Rhoran on April 10, 2019, 11:09 AM
I was just about to start a thread asking the same question. It's a shame we won't even see any attempts at implementation until at least 1.12 if I am interpreting the page correctly. At this time, we're on 1.10. I'd rather not go back to 1.8 just for save states, but that seems to be the case.
Title: Re: Save states on SD2Snes
Post by: Kobe on October 23, 2019, 10:16 PM
So what is going on in regards to the save states? I downloaded the 1.8 firmware and don't have any options for in game save states, what the heck?
Title: Re: Save states on SD2Snes
Post by: Relikk on October 23, 2019, 10:48 PM
Save states were never official, they were worked on by a third party, thus never released in official firmware. A guy called FURiOUS was the developer.

https://twitter.com/furious_/status/1050002481420427265
Title: Re: Save states on SD2Snes
Post by: Kobe on October 24, 2019, 03:20 AM
^Thank you for that, thanks to using save states I was finally able to beat Castlevania IV!

Here's hoping that they'll implement this feature in an official firmware update- obviously it won't be perfect, but having it makes some games much more enjoyable for someone like me who doesn't have all the time in the world to master each game.
Title: Re: Save states on SD2Snes
Post by: Relikk on October 24, 2019, 09:40 AM
Here's hoping that they'll implement this feature in an official firmware update- obviously it won't be perfect, but having it makes some games much more enjoyable for someone like me who doesn't have all the time in the world to master each game.

There's a lot of communication lately between FURiOUS and ikari on Discord. They're working on it. It might take a while, but it'll happen. Give it time.
Title: Re: Save states on SD2Snes
Post by: leonquest on October 24, 2019, 10:53 PM
^Thank you for that, thanks to using save states I was finally able to beat Castlevania IV!

Here's hoping that they'll implement this feature in an official firmware update- obviously it won't be perfect, but having it makes some games much more enjoyable for someone like me who doesn't have all the time in the world to master each game.

- Castlevania 4 is a difficult game? don't go playing the NES ones. ;)

- After you get past a certain age, you realize it's not about the destination but the ride. These classic games are still awesome to play whether you ever finish them or not, this is why I personally have spent so much of what little money I make on classic consoles.

But I'm not critizing you though, to each his own. Save states are tons of fun for many different reasons.
Title: Re: Save states on SD2Snes
Post by: nuu on October 25, 2019, 03:35 PM
That's why I think save states ruins the games if they are abused, like when used for getting past a tough part or used for extending credits. And Super Castlevania IV has passwords so it doesn't even need save states for saving progress when you stop playing.
Title: Re: Save states on SD2Snes
Post by: leonquest on October 25, 2019, 07:27 PM
That's why I think save states ruins the games if they are abused, like when used for getting past a tough part or used for extending credits. And Super Castlevania IV has passwords so it doesn't even need save states for saving progress when you stop playing.

I learned that hard lesson on the late 90s/early 00s when the emulation age came about. Now we have everdrives for more than just nostalgia: to us old games are objectively better than a lot of the modern stuff being made, so save states are more for fun than to actually finish difficult games.
Title: Re: Save states on SD2Snes
Post by: Kobe on October 25, 2019, 09:33 PM
^Thank you for that, thanks to using save states I was finally able to beat Castlevania IV!

Here's hoping that they'll implement this feature in an official firmware update- obviously it won't be perfect, but having it makes some games much more enjoyable for someone like me who doesn't have all the time in the world to master each game.

- Castlevania 4 is a difficult game? don't go playing the NES ones. ;)

- After you get past a certain age, you realize it's not about the destination but the ride. These classic games are still awesome to play whether you ever finish them or not, this is why I personally have spent so much of what little money I make on classic consoles.

But I'm not critizing you though, to each his own. Save states are tons of fun for many different reasons.
I'm going through the Castlevania games in order of release, so yes, I beat the 3 NES/Famicom games but also using save states. Just 100% Rondo of Blood on my PC Engine (no save states used there). I have no issues with using them, if I didn't I would never complete these games, and I would probably just curse the game out and never play them again. I make no apologies about using them, I'm not trying to prove anything to anyone. I'm just trying to play the games, enjoy them, and complete them because I want to go on to the next one. And with so many thousands of games I want to play, this is the only way I can feasibly get through them. So if you are against using them, all the power to you. But for me, I'm just trying to enjoy my gameplay time, because I have an extremely limited time now that I can devote to playing games and I have so many to go through.
Title: Re: Save states on SD2Snes
Post by: leonquest on October 25, 2019, 10:46 PM
^Thank you for that, thanks to using save states I was finally able to beat Castlevania IV!

Here's hoping that they'll implement this feature in an official firmware update- obviously it won't be perfect, but having it makes some games much more enjoyable for someone like me who doesn't have all the time in the world to master each game.

- Castlevania 4 is a difficult game? don't go playing the NES ones. ;)

- After you get past a certain age, you realize it's not about the destination but the ride. These classic games are still awesome to play whether you ever finish them or not, this is why I personally have spent so much of what little money I make on classic consoles.

But I'm not critizing you though, to each his own. Save states are tons of fun for many different reasons.
I'm going through the Castlevania games in order of release, so yes, I beat the 3 NES/Famicom games but also using save states. Just 100% Rondo of Blood on my PC Engine (no save states used there). I have no issues with using them, if I didn't I would never complete these games, and I would probably just curse the game out and never play them again. I make no apologies about using them, I'm not trying to prove anything to anyone. I'm just trying to play the games, enjoy them, and complete them because I want to go on to the next one. And with so many thousands of games I want to play, this is the only way I can feasibly get through them. So if you are against using them, all the power to you. But for me, I'm just trying to enjoy my gameplay time, because I have an extremely limited time now that I can devote to playing games and I have so many to go through.

You sound a little defensive, you must have missed the "I'm not critizing" part. Oh Well, more power to you.
Title: Re: Save states on SD2Snes
Post by: imafugyashizup on October 26, 2019, 12:29 PM
That's why I think save states ruins the games if they are abused, like when used for getting past a tough part or used for extending credits. And Super Castlevania IV has passwords so it doesn't even need save states for saving progress when you stop playing.

I got my pro last tuesday and I just finished earthbound tonight with it and gotta say, it felt much more rewarding not using save states through the end game. Especially not fast forwarding, which i love to abuse on grindy games. The frustration of the end really made it worth it. However* if you do really need to savestate an area, if the game has saves, just transfer the battery save back and forth(if your emulator is compatible).
Title: Re: Save states on SD2Snes
Post by: Sarge on October 26, 2019, 10:14 PM
If I'm out to beat a difficult game, I'll often use save states to practice the hard bits before making a legit run. It shortens the learning curve, especially in games like Battletoads or Ninja Gaiden III.
Title: Re: Save states on SD2Snes
Post by: nuu on October 27, 2019, 06:06 PM
I know what you all are talking about, I used to use tons of save states and fast-forwarding in emulators too. There are situations where they are really useful, for example if you just want to see the ending of a game that you don't seem to get anywhere in (Ghost and Goblins anyone?) or in an RPG where there are multiple options and you want to see all outcomes without having to play through the game again everytime, or to see other things that you might not normally be able to see. Yes and using them to save time when practising is also useful. That last one almost goes into the cheating-because-the-rules-are-broken category.

After learning to abuse them however you notice that games becomes boring doing so and it doesn't feel like you really beat the games. And even if you use save states just to save progress or so, it's quite easy to get into the habit and reload when you get a Game Over, just because you happened to have a quite recent save state.

Just 100% Rondo of Blood on my PC Engine (no save states used there).
If you can beat Rondo I see no reason why you shouldn't be able to beat IV. It was some time ago I played either of them but I think IV is probably easier.
The NES games are not too much harder than Rondo either. Especially the FDS version of the first game which can save, and the Famicom version of the third game is also easier than the NES version.
Title: Re: Save states on SD2Snes
Post by: Kobe on October 29, 2019, 10:51 PM
I could probably beat IV without save states, but that would require a lot more time investment (and added frustration). Like I said, I'm just trying to complete and enjoy the games at this point, have an extremely limited time to devote to any one game, literally have thousands of games I still need to play. This is what save states mean to me: Save time and frustration.
Title: Re: Save states on SD2Snes
Post by: duhmez on November 25, 2019, 11:13 AM
I tried the unofficial Save State firmware, 1.8 with SD2SNES pro, but I do not see any save state option int he menu.  Am I doing something wrong?  How do I test out the 3rd party save state firmware? I open the menu during game and see only the normal options.

What I have tried: I first puit the official firmware on there. Then I downloaeed and unzipped the save state firmware 1.8 in there.

The games work good and everythinbg, btu I see no save state option.  Am I doing something wrong or is the Pro not working with it?  Does anyone hav experience with this can help me out?
Title: Re: Save states on SD2Snes
Post by: Relikk on November 25, 2019, 11:37 AM
Am I doing something wrong or is the Pro not working with it?

The firmware was not for the Pro. It was for the original SD2SNES.
Title: Re: Save states on SD2Snes
Post by: duhmez on November 27, 2019, 04:09 AM
Am I doing something wrong or is the Pro not working with it?

The firmware was not for the Pro. It was for the original SD2SNES.
That is good to hear, that I am not crazy. The reason I asked was there was an earlier  poster that said they had it working on the pro model.
Title: Re: Save states on SD2Snes
Post by: JonIIDX on February 11, 2020, 03:51 PM
Hey everyone. :>

Any update about Save State support on the SD2SNES Pro/FXPak Pro? Guessing no... While many people use save states to clear games, many other people use save states to practice strats for speedrunning or other forms of gameplay. Whether you want to use savestates or not, the ability to choose to use them is a huge factor of why I haven't bought this loader yet.

However, I have heard that USB2SNES (http://usb2snes.com/ (http://usb2snes.com/)) used in tandem with Savestate2SNES (https://skarsnik.github.io/Savestate2snes/ (https://skarsnik.github.io/Savestate2snes/)) allows you to use savestates if you hook your SD2SNES Pro (FXPak Pro) to the computer. While it would be great if the official firmware would support even a beta functionality of savestates, at least there seems to be some kind of work around.

Still have no idea if the latest build of USB2SNES (v11) works with the latest build of Savestate2SNES (v10). I guess I will have to buy the FXPak Pro and test for myself to find out... :/
Title: Re: Save states on SD2Snes
Post by: Galron on February 12, 2020, 06:20 AM
It's supposedly to be included in the firmware update, but there is no ETA on when that is going to be released.
Title: Re: Save states on SD2Snes
Post by: FartPuff on February 15, 2020, 11:23 PM
It's supposedly to be included in the firmware update, but there is no ETA on when that is going to be released.

can't wait!  :)
Title: Re: Save states on SD2Snes
Post by: mprziv on February 18, 2020, 02:46 PM
It's supposedly to be included in the firmware update, but there is no ETA on when that is going to be released.

Just picked up my FXPAK Pro to use with my Super NT. I was a little bummed that it doesn't support save states, since the SD2SNES does. Really looking forward to future updates. Thanks to the devs for supporting this!
Title: Re: Save states on SD2Snes
Post by: Galron on February 19, 2020, 08:06 AM
Quote
since the SD2SNES does

Only marginally, only on an outdated 'fork' of the drivers made by a 3rd party. It's apparenlty hit and miss, and doesn't work on SA1 or special chips from what I understand? You'll be better off with the newer official firmwares for compatilbity reasons.

There is no 'official' support for save states. The upcoming firmware will be the first official release of save states, and apparently have better compatiblity and less buggy. It will access sound differently.
Title: Re: Save states on SD2Snes
Post by: Richardragon87 on February 19, 2020, 10:09 PM
It's supposedly to be included in the firmware update, but there is no ETA on when that is going to be released.

Just picked up my FXPAK Pro to use with my Super NT. I was a little bummed that it doesn't support save states, since the SD2SNES does. Really looking forward to future updates. Thanks to the devs for supporting this!

Officially the SD2SNES has never had that feature incorporated into it as it was just a unofficial add on that was never distributed in the proper updates for the SD2 SNES. The only thing the SD2SNES does what the FXPAK doesn't was that it used a regular sized SD card making it easy to take in and out for updates while the later one used a micro SD that was more useful on devices that were no bigger than a GB series size that would require too much space for other chips that were used.
Title: Re: Save states on SD2Snes
Post by: nuu on February 20, 2020, 01:28 PM
It will access sound differently.
This will probably introduce new incompatibilities, and it's just a really bad thing for homebrew developers that wants to test on the real APU. I just hope that it will be possible to use the SNES APU like normal as well when disabling save states.
Title: Re: Save states on SD2Snes
Post by: Galron on February 24, 2020, 09:22 AM
NUU, not sure how it works.. I think the issue was before save states intereferred with sound channels, or how the system accessed sound. The idea is to now accesss a different form of save states, that won't interfere with the normal function of sound system (as the previous attempts did). But it may also 'save state' the sound as well. This may only be capable on the Pro version though. Who knows, what it will do though, its only briefly been discussed in an interview with Smokemonster. We'll just have to wait and see...

Other possibilities on pro might be able ot save state on special chip games.
Title: Re: Save states on SD2Snes
Post by: nuu on February 24, 2020, 09:49 PM
No it didn't interfere with the sound channels, the problem with save states on the SNES using a flashcart is that there is no good way to know the exact state of the APU from the cartridge. So sound will break when making a save state because you can't preserve the sound program's state. In that interview with Smokemonster it sounded like they were going to program an FPGA APU which the game will think is the APU and upload its sound program and sound data to.

It's easy to preserve the state of this FPGA-simulated APU in the save state since it's part of the flashcart's workings. But that also means sound is not playing on your SNES hardware but on an FPGA APU in the SD2SNES. Any homebrew testing or APU comparisons would be useless. That's why it's a bad thing. If it's just an option it's ok though.
Title: Re: Save states on SD2Snes
Post by: FartPuff on March 01, 2020, 05:42 AM
No it didn't interfere with the sound channels, the problem with save states on the SNES using a flashcart is that there is no good way to know the exact state of the APU from the cartridge. So sound will break when making a save state because you can't preserve the sound program's state. In that interview with Smokemonster it sounded like they were going to program an FPGA APU which the game will think is the APU and upload its sound program and sound data to.

It's easy to preserve the state of this FPGA-simulated APU in the save state since it's part of the flashcart's workings. But that also means sound is not playing on your SNES hardware but on an FPGA APU in the SD2SNES. Any homebrew testing or APU comparisons would be useless. That's why it's a bad thing. If it's just an option it's ok though.

I thought that this problem was only with MSU1 - SNES Media Streaming Unit  for the reason you stated, but stock ROMs don't have the problem?
Title: Re: Save states on SD2Snes
Post by: nuu on March 01, 2020, 01:09 PM
No it's only a problem with the SNES APU. The MSU1 is part of the flashcartridge so there is no problem for it to preserve the state of it.
Title: Re: Save states on SD2Snes
Post by: WaveRacer on March 02, 2020, 11:57 AM
I thought the plan for the FPGA APU would be to mirror any sound commands issued to it so it runs in tandem with the real SPC chip in the SNES, it wouldn't then actually output any sound (the real chip would continue to do that) and it would just be there so the save state system has something to capture from.
Title: Re: Save states on SD2Snes
Post by: nuu on March 02, 2020, 05:13 PM
You mean it would only be tracking the sound data sent to the APU so that it knows the state of the APU? That sounds like a much better solution, but it's not what I've heard.

Here is the relevant interview part:
Quote from: Ikari
I hope to overcome this limitation by running my own APU implementation on the FPGA which makes me the “owner” of its state too, so I can grab it whenever I want.
The original APU would be silenced by running a little hook on reset that uploads an infinite loop so it doesn’t react to any CPU access. The sd2snes would then override the bus with its own APU responses accordingly.
https://www.retrorgb.com/sd2snes-pro-more-details-from-ikari.html

If it's not made as an optional feature, it's a reprehensible update only useful for certain customers.
Title: Re: Save states on SD2Snes
Post by: WaveRacer on March 02, 2020, 09:31 PM
Yeah that does sound like the plan is to just bypass using the internal audio altogether. :'( But how would that implementation get the sound from the FPGA through the cartridge slot and out the sound channels?
Title: Re: Save states on SD2Snes
Post by: nuu on March 03, 2020, 12:58 AM
I suppose audio output is connected to the cartridge connector like on Famicom.