the SNES expansion port?
I'm planning to learn NESasm, SNESasm, and then call a friend of mine who knows a lot about hardware, we plan to do a SNES-CD.
I was thinking about using a Z80 for processor (even some people in the NESDev board said it was confusing to use) and build some devtools that could make Game Making for it as easy as eating pie.
The design tool would be (or will if i can build it) the sort of thing that Game Maker is for PC. Less coding, more gaming.
The extra APU would be the same the Mega Drive uses, the YM2612 (Yes, that's right. I love the meow sound of this chip)
Extra GPU? YM7101.
This might be just a dream, but i would like to know if it is possible...
So, you'll essentially be turning the SNES into a Mega Drive? What's the point really?
Z80 is pretty inefficient, why not make it another 6502 so you don't have to use 2 completely different chips on it? And what needs added on that the SNES can't do by it's self? Also, it works differently from 65 chips, so you may want to see if it's even doable within X ammount of parts.
So, other CPU, other audio, other graphics - completely new system. How this would relate to SNES then?
It doesn't look like the SNES expansion port has an address. I guess you would decode the address on your cartridge, then send the enable signal through the "EXPAND" pin.
I'd sorta complain about using a Z80 for that too, unless it performs notably better than the SNES CPU it doesn't seem all that interesting. The video and sound registers might as well be mapped to the SNES directly, so it can get straight to it. I think a better CPU would be something like the MIPS or ARM. They should be fast enough to emulate a Z80 or 6502, if one didn't want to program in native assembly or C.
Even better would be using an FPGA to recreate all those (or create new) functions in a single chip.
Sure any of this stuff is possible, but just depends on what you want to do with it.
There are those clone systems around that include an SNES and Genesis inside, maybe there would be some way to modify it and bridge the systems?
Find the 28-pin female socket connectors for the expansion port, sell a hundred to me (with profit markup), and I'll tell you anything you want to know about it =)
Without the connectors, you won't be able to get anywhere. They are impossible to come by.
Ok, the specs were pure shite, it's because i saw some threads discussing Full Motion Video on SNES, especially byuu, who wrote that interesting add-on to play FMV. And so i thought a SNESCD would do a great job. What do you guys think? Pure dreams or maybe true?
Reply to byuu:
Getting the 80th!
EDIT: What a good time to have my SNES broken, eh? Lil' bastard turned from NTSC to PAL 'cause i used some obscure f-zero cart! Video
here, please help!
Memblers wrote:
There are those clone systems around that include an SNES and Genesis inside, maybe there would be some way to modify it and bridge the systems?
Genintendo? Or Super Drive? Sounds great...
A SNES doesn't somehow change from an NTSC model to a PAL because of some game you played.
Maybe you got connector dirty with that cart. Or maybe you physically broke the connector.
Or it could be some other hardware failure unrelated to plugging in that cart.
Sorry guys, but i can't stop posting.
It looks like my SNES is with a very old cart slot. I also upped an image of the obscure f-zero cart here:
Seriously, and it wasn't even criminal market. Strange enough, in Brazil our carts are similar to the American ones, and this looks European, here is the picture of it open.
And now, we can see the cart broke. Anyone can tell me if my SNES can still be fixed? Also, the EEPROM was REALLY cheap. Doesn't F-zero uses a special chip? Forget it. I didn't find any special chip on it. just a Taiwan made EEPROM with FO written on it.
Sorry for big pics!
mic_ wrote:
A SNES doesn't somehow change from an NTSC model to a PAL because of some game you played.
Maybe you got connector dirty with that cart. Or maybe you physically broke the connector.
Or it could be some other hardware failure unrelated to plugging in that cart.
So i should try what? You saw the pics? The cart pins are black. How do i clean my connector?
You wouldn't happen to be (possibly related to)
this guy, would you?
byuu wrote:
You wouldn't happen to be (possibly related to)
this guy, would you?
Not a chance. I don't even know this guy. I just want help to fix my SNES, and try to make games for NES and SNES... Oh boy, i miss playing "S.T.G. Strike Gunner"...
edit: Oops, got the title of the game wrong!
mic_ sure is right. The freaking cart made my connector as dirty as Leisure Suit Larry. Oh noes! What do i do now? Which tools i must use? (Please, don't say SNES Cleaning Kit, in Santos, no way to buy it!)
Edit/add: Interesting though the system's running on PAL-M mode, the sound is not slowed down. The APU and CPU work just fine, but the GPU's got problem.
Shiru wrote:
So, other CPU, other audio, other graphics - completely new system. How this would relate to SNES then?
The original PlayStation was originally a CD drive for the Super NES before Sony retooled it not to require a Super NES.
Memblers wrote:
I think a better CPU would be something like the MIPS or ARM.
And guess what's in the original PlayStation.
IvanDSM: Did rubbing alcohol (isopropanol 70%) on a cotton swab work?
If you want to use CDROM with SNES, try using the PC-Engine CDROM. I bet it could work. Sega CD has alot more going on with it. But in the end it will just be a neat gimmick since you would have no real games and no real production of the device more than likely.
tepples, i'll try doing that.
MottZilla, so it just wouldn't work?
IvanDSM wrote:
tepples, i'll try doing that.
MottZilla, so it just wouldn't work?
You do know to add a CD to it would require you to also program it and then also incorporate it into a program of some sort....right?
3gengames wrote:
IvanDSM wrote:
tepples, i'll try doing that.
MottZilla, so it just wouldn't work?
You do know to add a CD to it would require you to also program it and then also incorporate it into a program of some sort....right?
Oh shot... Now i understand you guys, i don't have a bit of experience in ASM, i'm just dreaming, anyway, thanks for the tips to fix the SNES!
IvanDSM wrote:
Interesting though the system's running on PAL-M mode, the sound is not slowed down.
PAL-M is 60Hz, just like NTSC, so there's no reason for slowdowns.
tokumaru wrote:
IvanDSM wrote:
Interesting though the system's running on PAL-M mode, the sound is not slowed down.
PAL-M is 60Hz, just like NTSC, so there's no reason for slowdowns.
Oh, thanks!
I thought every PAL was 50hz.
Simple question:
What exactly is your intended purpose behind hooking up and being able to utilise a CD-ROM drive on a SNES/SFC?
You're not going to be happy to hear what I have to say if you're doing it for the reasons I think you are...
Quote:
You're not going to be happy to hear what I have to say if you're doing it for the reasons I think you are...
Let me guess : Pass it as an "authentic Playstation beta devkit" and sell it for a very high price ?
koitsu wrote:
You're not going to be happy to hear what I have to say if you're doing it for the reasons I think you are...
But koitsu! Throw in an nVidia 580 GTX, Core i7, SoundBlaster X-Fi, CD-storage, and your SNES will be absolutely ROCKING with that 21KB/frame video transfer rate! (2.48MB/s B-bus->A-bus, cut in half for sending via A-bus->PPU, 60fps.) Imagine those beautiful 3D renders in glorious RGB332 / 224x144 @ 30fps.
(Or route the video through your new device, and treat the SNES like a glorified controller port. Because why not?)
Quote:
(Or route the video through your new device, and treat the SNES like a glorified controller port. Because why not?)
That's pretty much what the Super Game Boy does I guess.
No fake beta thing, i was just thinking on it for some kind of expansion...
A 2nd project was to make it accept Audio CDs, VCDs, SVCDs and exploring CD-ROMS with the ability of opening video and sound files.
If i wanted to do a fake device i would ask "How can i make a SNES-CD that plays Never Gonna Give You Up
upon loaded?"
Edit: Just for fun, SNES itself has a hell emulator. Just disassemble the EJECT button (Only American ones, no European or Japanese!) and TRY to make it again. Welcome to hell!
IvanDSM wrote:
Edit: Just for fun, SNES itself has a hell emulator. Just disassemble the EJECT button (Only American ones, no European or Japanese!) and TRY to make it again. Welcome to hell!
Ok...lost me there. Lurking++.
Bregalad wrote:
Quote:
You're not going to be happy to hear what I have to say if you're doing it for the reasons I think you are...
Let me guess : Pass it as an "authentic Playstation beta devkit" and sell it for a very high price ?
Nah -- byuu's response was spot on, and is also one of the original reasons why Nintendo scrapped the Play Station (CD drive for the SNES/SFC). And no that name isn't a typo.
IvanDSM wrote:
No fake beta thing, i was just thinking on it for some kind of expansion...
A 2nd project was to make it accept Audio CDs, VCDs, SVCDs and exploring CD-ROMS with the ability of opening video and sound files.
If i wanted to do a fake device i would ask "How can i make a SNES-CD that plays Never Gonna Give You Up
upon loaded?"
Edit: Just for fun, SNES itself has a hell emulator. Just disassemble the EJECT button (Only American ones, no European or Japanese!) and TRY to make it again. Welcome to hell!
And that's exactly what I thought you were going to say. :(
How do you plan on solving the bus bandwidth issue? As byuu said, you've got about 21KBytes/sec worth of bandwidth between the PPU and main system memory.
This is one of the reasons Nintendo originally scrapped their CD drive for the SNES/SFC (which was originally called the Play Station, made by Sony -- no joke). There wasn't enough bus bandwidth to do full-screen video playback. I'm not making this up. It's difficult to find confirmation on the web of this, but
this is pretty much the best explanation. Watch the entire video, don't skip around.
So, good luck with this project... (where's the little emoticon with rolling eyes? Oh that's some other forum software)
koitsu, i know about the Play Station story and all the issues with PHILIPS and SONY from SNES-CD.
IvanDSM wrote:
If i wanted to do a fake device i would ask "How can i make a SNES-CD that plays Never Gonna Give You Up
upon loaded?"
You don't need a CD for that. Nor do you even need a Super NES, really. All you really have to do is put
Kirby's hamster friend and
Dr. Light's robotic housekeeper in the same game.
Read more
byuu: I'm pretty sure that more than 224x144 is possible, at the expense of a bit of grain. Choose a few palettes that represent parts of the image and assign them.
Smashing.
tepples wrote:
IvanDSM wrote:
If i wanted to do a fake device i would ask "How can i make a SNES-CD that plays Never Gonna Give You Up
upon loaded?"
You don't need a CD for that. Nor do you even need a Super NES, really. All you really have to do is put
Kirby's hamster friend and
Dr. Light's robotic housekeeper in the same game.
Read more
I know that rom. It is really stunning. Can we keep an entire track on NES? Like Yellow Submarine? Please don't refer to 2-in-1 Streetdance and Hit Mouse. That shit annoys me. The sound quality is so bad i'd puke on the cart.
Edit (Add): And the point of that message is that if i wanted to do a fake device, i'd do one that played the whole track, so it would rick roll the guy who buyed it.
Bregalad wrote:
That's pretty much what the Super Game Boy does I guess.
Uhh, no? The Tristar NES or whatever does this, but the SGB uses the SNES PPU.
koitsu wrote:
There wasn't enough bus bandwidth to do full-screen video playback.
Yeah, it would basically be like the Mega CD, only more limited. SNES is further crippled by VRAM being off-limits during screen rendering, so even heavy sprite rotation wouldn't be practical.
The only thing an add-on unit could do better than say a SuperFX/SA-1 would be CD-audio playback and lots and lots of raw data that carry those fun "loading, please wait" screens. It's further crippled because both the expansion port and PPU+APU are on the B-bus, so you have to doubly transfer all data.
MSU1 is basically everything the SNES CD could have offered, except in the cart on the A-bus, so you double your potential with direct-to-VRAM transfers. It's enough to pull off dithered 60%-fullscreen video, which is passable for animated video, but doesn't hold a candle to PSX/Saturn MPEG video.
The SNES-CD would further need a lossy video decoder to handle the 2.48MB/s throughput rate and smaller storage pool (700MB), making the 224x144x8bpp@30fps output even more pathetic. Also must keep in mind that the SPC700 can put out amazing sound already. It wouldn't be as huge a gain as it was for the Mega Drive.
In my opinion the main gain for a SNES CD would have been the storage. ROM Memory was expensive and plenty of games certainly had to make cuts because of this. While it was an early game Final Fight suffered because of the 8M of ROM was not big enough to fit an entire level as well as a 3rd player character plus I recall hearing it may have been a reason for the low sound quality particularly of the music.
Another thing byuu while you mention the SPC's great quality, it's still limited by the 64K of memory. Isn't the reason Street Fighter Alpha 2 has those strange pauses due to loading SPC memory? If you played music off a CD you could save alot of memory not needing samples for music instruments or pattern data for playing the music or code for playing it. You'd have much more room for high quality sound effects, plus more sound channels for them.
But it doesn't matter now, it's not like if you made a SNES CD that suddenly there would be games for it. About MSU1, I've heard of some projects using it to add FMV and CD quality audio. Wasn't someone putting Chrono Trigger's PSX FMVs into it? And I thought I heard something about Der Langrisser too.
CD storage won't help you that much with games. You are limited to 1-2x transfer rates, have terrible seek delays with no random access, and only have 128K RAM to buffer, most of which is used by your game engine already. Only way to make it shine would be to stick a 64MB RAM+MMC chip in the cartridge slot to buffer your game and eliminate loading times during play. And that'd cost a fortune back then, and you couldn't make anything more visually impressive because you have the same PPU. And for what? FF6 @ 3MB was already 40 hours of gameplay. Would we seriously expect 200-hour RPGs with this added storage?
Much as I love the SNES, I have to agree that the SNES-CD concept made no sense. It would have bombed like the Mega CD.
Re: MSU1, yeah it's basically meant to enhance existing games. I've made patches to replace the SPC soundtracks (leaving sound effects intact) in Earthbound and Der Langrisser, and smkdan inserted the CT PSX intro into the SNES version on the older 21fx API. Super Mario Odyssey's a custom SMW ROM hack that uses it as well.
Progress hasn't been too rapid because only bsnes can use it so far. Planning to try and pick things up a bit more once the sd2snes goes on sale.
The PC-Engine CD attachment was fairly successful. In the end I agree that cost ultimately made these CD attachments doomed to be a niche product. But PC-Engine's CD was nothing more than CDROM storage, audio, and a bunch of RAM for loading the game into. If you had a cartridge with a large amount of memory, 8 or 16 megabits, I think you could have some nice games on SNES. But that's not to say that they would be vastly better. Afterall, storage problems were attacked by compression too with SDD-1 and other means.
That's really what it is about, having more room for level data, graphics animation, and CD audio. Sega CD took it further by adding a second CPU and other things.
It'll be neat to see what happens when the SD2SNES cartridge comes out.
MottZilla is right. The FDS came with a 40 KB system card, the PCE CD had 64 KB plus a 192 KB Super System Card (built-in on the Duo), and the Sega CD had 768 KB. The Play Station would have probably used such a system card.
How about T.I.M.E.? (Is that the way it's written) How did it control the audio tracks? Or did YOU have to play the track manuallly?