128mbit game possible?

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MottZilla
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Re: 128mbit game possible?

Post by MottZilla »

MAD-1 doesn't control HiROM/LoROM connection of the actual eproms. You need to connect two of them as I said, in HiROM fashion and the final one in LoROM fashion (skipping A15 on the socket). If you wired all 3 roms address lines exactly the same/all together then it won't work properly. Perhaps all that was wrong was you connected the upper address lines on ROM 3 incorrectly (non LoROM fashion).
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getafixx
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Re: 128mbit game possible?

Post by getafixx »

Alright, I will give that a try and report back.
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getafixx
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Re: 128mbit game possible?

Post by getafixx »

Well...i feel sheepish. That's all it was, just the 3rd rom was wired as Hirom instead of Lorom. :oops:

Thanks for pointing out that obvious step to me Mott!

Just one last question about this, and this is probably aimed more at shadowkn55. It's been mentioned on here a few times that the SNES can only access about ~95Mbit of data, so being that this game is 96Mbit, will there be issues with it crashing or glitching later on? Has anyone played it on an actual cart long enough to see?

EDIT: I just re-read a pm I got from Shadowkn55 a few months ago, and he stated that he did indeed play the game through to the end, and it worked. He did mention a couple times where the cart crashed, but he figured it was due to power consumption issues, as he said the cart never crashed twice in the same place. To avoid this, I'm going to run thicker VCC and GND wires to my roms and see if that takes care of it. The other thing might be adding some caps to take care of potential noise.
Last edited by getafixx on Thu Feb 28, 2013 4:28 pm, edited 1 time in total.
tepples
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Re: 128mbit game possible?

Post by tepples »

A well-formed patch will just have no data in the 1 Mbit hole where the internal RAM is ($7E0000-$7FFFFF).
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MottZilla
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Re: 128mbit game possible?

Post by MottZilla »

That last bit of ROM is never accessed. The 96Meg hack as far as I've heard is fully playable.
Markfrizb
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Re:

Post by Markfrizb »

kyuusaku wrote:I've come up with a REALLY easy 96M ROM + SRAM decoder using the 139 already in many SNES carts:

Image

Clever huh? It doesn't look like SRAM will conflict with anything but I'm going by internet memory maps.

while visiting this topic (again), I was drawing up a schematic for the star ocean cart and I noticed 2 different approaches to using the 139. The above pic and below post........

1. MAD-1 #4
2. MAD-1 #12
3. GND
4. ROM 3(00-3F/80-BF:8000-FFFF)
5. Connected to Pin 15
6. NC
7. NC
8. GND
9. NC
10. NC
11. ROM 1(C0-FF:0000-FFFF)
12. ROM 2(40-7D:0000-FFFF)
13. GND
14. A23
15. Connected to Pin 5
16. VCC


so my question is.......do both methods work? Getafixx tried the method illustrated in the pic and said it worked. I believe it uses the mad1 although it's not referenced. obviously, the other method (in green) uses the mad1.

thanks!
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bazz
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Re: Re:

Post by bazz »

Markfrizb wrote:
kyuusaku wrote:I've come up with a REALLY easy 96M ROM + SRAM decoder using the 139 already in many SNES carts:

Image

Clever huh? It doesn't look like SRAM will conflict with anything but I'm going by internet memory maps.

while visiting this topic (again), I was drawing up a schematic for the star ocean cart and I noticed 2 different approaches to using the 139. The above pic and below post........

1. MAD-1 #4
2. MAD-1 #12
3. GND
4. ROM 3(00-3F/80-BF:8000-FFFF)
5. Connected to Pin 15
6. NC
7. NC
8. GND
9. NC
10. NC
11. ROM 1(C0-FF:0000-FFFF)
12. ROM 2(40-7D:0000-FFFF)
13. GND
14. A23
15. Connected to Pin 5
16. VCC


so my question is.......do both methods work? Getafixx tried the method illustrated in the pic and said it worked. I believe it uses the mad1 although it's not referenced. obviously, the other method (in green) uses the mad1.

thanks!
Hey Mark I have begun reviewing such a 96Mb cartridge, and the first mapper without the MAD-1. It doesn't use a MAD-1 at all. I detailed the ROM pinouts here: http://www.cs.umb.edu/~bazz/snes/96MbCart/

see derp.html
RedScorpion
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Re: 128mbit game possible?

Post by RedScorpion »

hi,

sorry that i pick up this old thread, but i read all pages and have a last question.

The max ist 64MB(Eprom) + 32MB(Eprom) + 8MB SRAM

Would that mean have to use 1x 8MB Eprom + 1 x 4MB Eprom (i.e.27c322?)

Or could you use 2x27C322 + 1x 27C322 eproms?!

Has anyone built a 96 Star Ocean Cart with this solultion?!

Thanks

red
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infiniteneslives
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Re: 128mbit game possible?

Post by infiniteneslives »

Anything totaling to atleast 128Mbit that places the rom image in all the right spots should be capable of working. 3x32Mb, 1x64Mb + 1x32Mb, 6x16Mb, 1x128Mb with wasted space, it's all the same in the eyes of the SNES if its all decoded properly with the expected data.
If you're gonna play the Game Boy, you gotta learn to play it right. -Kenny Rogers
slobu
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Re: 128mbit game possible?

Post by slobu »

infiniteneslives wrote:Anything totaling to atleast 128Mbit that places the rom image in all the right spots should be capable of working. 3x32Mb, 1x64Mb + 1x32Mb, 6x16Mb, 1x128Mb with wasted space, it's all the same in the eyes of the SNES if its all decoded properly with the expected data.
So, there isn't a billion "mappers" like NES? It's just the speed of the ROM?
tepples
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Re: 128mbit game possible?

Post by tepples »

For games with 32 Mbit or smaller ROM and no coprocessor that aren't weird multicarts, the two "mappers" you really have to deal with are LoROM (skip A15) and HiROM (skip A22).

The total 65816 address space is 128 Mbit. Subtracting areas reserved for the console (banks $7E and $7F and the first half of $00-$3F and $80-$BF) leaves 95 Mbit. For anything bigger than that, you'll need a Real Mapper of some sort.
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infiniteneslives
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Re: 128mbit game possible?

Post by infiniteneslives »

My post was in reference to a 128Mbit game that didn't have any co-processors as Tepples brought up. Exotic SNES carts (non Hi/Lo ROM) often have co-processors in comparison to the NES's 'memory mappers'. See wiki if you've got one of those my statement is null and void. I'm not certain, but I'd guess that over 95% of SNES games don't have any special chip/co-processor and are just plain rom uniquely mapped to the SNES memory space (don't forget all important mirroring though) via an address decoder such as the MAD.
If you're gonna play the Game Boy, you gotta learn to play it right. -Kenny Rogers
slobu
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Re: 128mbit game possible?

Post by slobu »

Sorry for being a little off topic. Actually, the SNES Hi/Lo-ROM reproduction flash boards from infinitelives can go up to 128mbit so it's nearly there :)

Is there a way to see at runtime if a genuine infinitelives repro board is in use?
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infiniteneslives
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Re: 128mbit game possible?

Post by infiniteneslives »

slobu wrote:Sorry for being a little off topic. Actually, the SNES Hi/Lo-ROM reproduction flash boards from infinitelives can go up to 128mbit so it's nearly there :)
Well they've got support for up to 128Mbit of flash memory, they could be configured to fill as much of the unused system space as possible though. But as Tepples pointed out you'll never be able to see all that 128Mbit worth at one time. By banking it's possible to use it all though. My main motive was for stuffing a bunch of games on there for a multicart via reset toggling, but a select register could be implemented as well similar to NES memory mappers. That and it didn't cost anything in regards to the design once two flash chips were draw out aside from a CPLD pin which was already available.
Is there a way to see at runtime if a genuine infinitelives repro board is in use?
It depends on how I configured it I suppose. With some games you actually need to be undetectable to run (SRAM size and mirroring mostly). I'm about to publish exactly how things are configured on all the different 'standard' size choices. So verifing that config would be possible. Probably closer to you goal though would be to read the device ID off of the flash chips. Granted using the same flash chips would get around that, but the memories I use are not compatible with typical TSOP to DIP adapters because they're 48 pin TSOP's. But that doesn't stop one from making one that would work. There is other trickery that could be inserted into the CPLD as well I suppose, but not likely to be done on my production boards.
If you're gonna play the Game Boy, you gotta learn to play it right. -Kenny Rogers
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MaarioS
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Re: 128mbit game possible?

Post by MaarioS »

Hey there people, I've read the entire topic but I still have not found the exact plain solution how to make Star Ocean cart. Well maybe there were some theories and debates but nothing 100% confirmed to be working on real hardware so.... has anyone figured out which portions of the code goes where?? How EXACTLY roms should be connected on the cart and which part of the code goes where?? Which part should be connected like normal and which part should be interleaved or connected different?? How about if I want to use combination of 8MB+4MB memories or even one 16MB memory?? I got kind of lost and now I have no idea what I'm supposed to do after reading all of this. I'd be so grateful if anyone made it very clear how to do the cart and provided me with confirmed & verified information. That would be so much appreciated!! Many thanks in advance!!
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