BS-X technical discussion

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tetsuo55
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BS-X technical discussion

Post by tetsuo55 »

i think its best to start a new thread for this so here goes.
i think we have to make sure the roms are accurate themselves.

okay my first question is:

How did BSX games know their timelimits, and how did the self-destruct work?

Was it stored in some kind of header? was the data appended to the rom? i personally have no clue.

First order of business:
try to isolate the BS-X lifespan data from the game data.
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Re: BS-X technical discussion

Post by Nach »

tetsuo55 wrote: i think we have to make sure the roms are accurate themselves.
There were no ROMs. Make sure you're very clear on that point.
tetsuo55 wrote: How did BSX games know their timelimits, and how did the self-destruct work?
Date it was downloaded was stuck in the game's internal header. It self destructed once the amount of time of play elapsed, and set a no longer working bit.
May 9 2007 - NSRT 3.4, now with lots of hashing and even more accurate information! Go download it.
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tetsuo55
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Post by tetsuo55 »

So emulating that correctly would mean:

The header of the clean "Game image" does not have a date, and the "no longer working bit" is set to false

Current method:

Select BS-X game from the menu to play the game, Bsnes copies the rom in memory? Then appends the date to the internal header (like a soft-patch) then once the time-limit passes the game gets the not-working bit.

Then if you want to play the game again you have to start over.

Future method?:

Game gets loaded into BS-X, BS-X actually remembers the game like on real hardware (so next time i get to choose resume BS-X play from the menu instead of load new game), as long as the time-limit has not passed the game is playable, emulator silently updates the BS-X clock every time the emulator is started, but only if a game is loaded and still valid?

Nach, i know the games are technically not roms, but its less confusing to name them that (but i agree with you that its completely inaccurate)
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Post by neo_bahamut1985 »

Kind of weird how emulators manage "emulate" the BS-X since the games weren't actually "games" per se. So, am I safe to assume emulators have to use a hack BS-X games to load?
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Post by Nach »

tetsuo55 wrote:Bsnes copies the rom in memory?
No, it copies the image to memory.
tetsuo55 wrote: Nach, i know the games are technically not roms, but its less confusing to name them that
On the contrary, I find it more confusing to name them ROMs. In fact, we should get more used to using the term "ROM Image". I plan on using the term "ROM Image" in all my tools where applicable when I get a chance.

Now just picture this conversation I had an hour ago with my sister.

Code: Select all

<Sister> Nach, can you buy me a USB?
<Nach> You want me to buy you a jack? You doing some kind of hardware project?
<Sister> What? No. I just want the cord.
<Nach> Oh, you want a USB extension cord, okay.
<Sister> No, not an extension cord. You know those things you plug in?
<Nach> No, not really, what are you referring to?
<Sister> That thing I see you use to transfer files.
<Nach> Oh, you want a memory stick?
<Sister> No, not a memory stick.
<Nach> I'm not sure what you're talking about.
<Sister> You know what a Walkman is?
<Nach> Yes.
<Sister> You know what a Diskman is?
<Nach> You mean a CD Player?
<Sister> No, those devices with MP3.
<Nach> You want a CD Player which can also play MP3 files, and not just raw audio tracks?
<Sister> Excuse me? I want an MP3 with wires.
<Nach> An MP3 is a file format, is has no wires.
<Sister> What are you being stupid? Everyone knows an MP3 has wires.
<Nach> Are you referring to a portable audio player which has MP3 support, and can transfer files via USB?
<Sister> What's with all the technobabble? Yes, that's what I want.
Using imprecise terms only leads to confusion. You don't have to perpetuate it. I get enough of it from people who don't know technology but think they do confusing everyone around them, we don't need more of it from people that should know better.
May 9 2007 - NSRT 3.4, now with lots of hashing and even more accurate information! Go download it.
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Nach
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Post by Nach »

neo_bahamut1985 wrote:Kind of weird how emulators manage "emulate" the BS-X since the games weren't actually "games" per se.
Uh no, they were games.
May 9 2007 - NSRT 3.4, now with lots of hashing and even more accurate information! Go download it.
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neo_bahamut1985
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Post by neo_bahamut1985 »

What I meant were "ROMs"...
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tetsuo55
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Post by tetsuo55 »

I agree with you Nach,

your right about the accurate naming of the data

this was one of the main problems the mess/mame xml format had to overcome.

They chose for:

We have a file with data in it, this data is in fact the software, the data comes from a physical medium

By taking this approach the data file can be generic and contain everything from a rom to a laserdisk.

So in short, they just call it software, so in BS-X game it would be BS-X-software
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Post by DancemasterGlenn »

Nach's sister sounds cute *runs*
I bring the trouble.
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Post by MisterJones »

Nach's just being an ass, as I found her sister's request quite easy to understand. He really just needs to get out just a little more often, as then you'd learn the lingo used by everyone else.

Not that I certainly approve of such disgusting misuse (I really hate it), but saying it confuses anyone who's not a nerd unwilling to learn the actually applications of everyday technologies and their everyday used names is such a big fat lie.
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Post by wertigon »

Nach's just being an ass, as I found her sister's request quite easy to understand. He really just needs to get out just a little more often, as then you'd learn the lingo used by everyone else.
So you mean you actually managed to dechipher that "USB" really meant "MP3 player with a USB chord"? Wow... *bows to your gr34t 4nd sup3r10r l4ngu4g3 sk1llz*
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Post by FitzRoy »

Weren't there BS-X "games" that were nothing but data packs for other things? I tend to think "rom" is just a reference to any data taken from a cartridge-based system. By the way, isn't bs-x EEPROM? And isn't that the type of chip from which the images were taken?
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Post by MisterJones »

wertigon wrote:
Nach's just being an ass, as I found her sister's request quite easy to understand. He really just needs to get out just a little more often, as then you'd learn the lingo used by everyone else.
So you mean you actually managed to dechipher that "USB" really meant "MP3 player with a USB chord"? Wow... *bows to your gr34t 4nd sup3r10r l4ngu4g3 sk1llz*
Actually, yes, half of it. I'm quite used to these sort of conversations (intesive tech support to cavemen-esque accountants and lawyers are a good training field), so macabre lingo is quite natural to me. :P
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Post by creaothceann »

MisterJones wrote:to me
vSNES | Delphi 10 BPLs
bsnes launcher with recent files list
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Post by MisterJones »

creaothceann wrote:
MisterJones wrote:to me
Well.....
(intesive tech support to cavemen-esque accountants and lawyers are a good training field)
Which actually are a small sample of the much larger average people who use said jargon. Failing to acknowledge said fact is just being blindfolded.

So in short: thousands (millions?) of individuals speak like that. Live with it, like it or not.


Where is that seifer quote about burger king anyway? Fits well with "a portable audio player which has MP3 support, and can transfer files via USB ".
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tetsuo55
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Post by tetsuo55 »

FitzRoy wrote:Weren't there BS-X "games" that were nothing but data packs for other things? I tend to think "rom" is just a reference to any data taken from a cartridge-based system. By the way, isn't bs-x EEPROM? And isn't that the type of chip from which the images were taken?
This is exactly why we need to stop using hardware descriptions for software. imho "Software Container" is a much better description.

It takes account for the fact that in hardware any medium could have been used.
It takes account for the fact that not everything is game.
It takes account for the fact that we store a bunch of files in a folder/zip

The BS-X was basically a cart with a rom on it, so this should also be stored in a "Software Container" this particular software opens up extra slots for loading more software into it
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Post by FitzRoy »

tetsuo55 wrote: This is exactly why we need to stop using hardware descriptions for software. imho "Software Container" is a much better description.
Rom or ROM has become acceptable shorthand for "ROM image," and the context in which it's used makes it fairly clear when this is happening. It's no different than "MP3" being commonly used to refer to an "MP3 file," even though others might exist: MP3 encoding, MP3 decoding, MP3 support. "Hey, should I use MP3 or FLAC on this file after I rip it?" Clearly, the person is talking about MP3 encoding from this context. Not only is Nach's sister using shorthand on something which has never been acceptable (MP3 for MP3 player), it takes her a while to provide sufficient context (USB and wires). Misuse of shorthand or no context doesn't mean all shorthand should be abolished from speech. It saves a lot more time than is lost from confusion.
The BS-X was basically a cart with a rom on it, so this should also be stored in a "Software Container" this particular software opens up extra slots for loading more software into it
This is exactly how bsnes functions right now with the exception of the pcb being created from reading the rom rather than recognized from a representational file. The BS-X cartridge can be loaded by itself, or loaded with a BSMC cartridge inserted. The two cartridges are still fundamentally separate objects even when they're interfacing with each other.

Random question, can someone bluntly state what function the BS-X cart's PSRAM has? I need this for my pcb serials document.
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Post by neviksti »

FitzRoy wrote:Random question, can someone bluntly state what function the BS-X cart's PSRAM has? I need this for my pcb serials document.
PSRAM = Pseudo SRAM. It is dynamic ram with a controller in the chip so it appears on the outside to function as SRAM. This allows the "SRAM" to be much cheaper once you get into larger memory sizes.

I used to have pictures of the cartridges, and I thought the PSRAM is what held the games and data. Since I don't have a cartridge, let alone a picture, in front of me at the moment I can't speak with much authority. (I do vaguely remember it using the rarely touched EXPAND pad on the cartridge connector though.) It's a neat cart.
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Post by FitzRoy »

Picture of the board:
http://img148.imageshack.us/img148/4959 ... ew3yl1.jpg

So the maskrom houses the st. giga program, and the PSRAM is what temporarily stores the incoming data, some of which can be written onto an EEPROM expansion cart?
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Post by neviksti »

FitzRoy wrote:Picture of the board:
http://img148.imageshack.us/img148/4959 ... ew3yl1.jpg

So the maskrom houses the st. giga program, and the PSRAM is what temporarily stores the incoming data, some of which can be written onto an EEPROM expansion cart?
Wow! Thanks for sharing the picture.

Yes, the PSRAM clearly stores game data, just due to its size.
Here's a datasheet:
http://datasheet.digchip.com/740/740-3- ... LFP-10.pdf

It sounds like it was chosen to be able to store data battery backed as well. You'd have to trace out the cartridge connections to know for sure.

Notice cart pad 33 is used, this is the signal from the SNES console telling when the console is pausing to do a DRAM refresh cycle. This way the cartridge can refresh its DRAM at the same time so it can always be available to the cpu and appear like "SRAM".

The MM1134 is used to help with battery backup of the SRAM (and/or possibly the PSRAM here as mentioned above), as you've probably seen on other cartridges. The other chips are fairly self explanatory, so I guess that's it.

It also uses cart pad 57, which is the CPU_CLOCK. I'm not sure what it needs this for. Where does this line go?

Amazingly this is yet another cartridge that ignores the /CART line, which means it probably gives a lot of copiers trouble (and can possibly damage some hardware).

Would you mind posting a picture of the other side? I'm curious if I remembered correctly and it does use cart pad 2 (EXPAND). For the life of me I can't remember what that signalled in this system... maybe it was used to notify the base unit of an EEPROM cartridge? You'd have to trace the lines to see.
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Post by FitzRoy »

Not my images, I got them from some website a while back.

http://img179.imageshack.us/img179/7042 ... ew2ui9.jpg
tetsuo55
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Post by tetsuo55 »

Aside from the obvious satallaview issues.

What part of the BS-X is not accurately being emulated in Bsnes?

(In other words why do some games have black screens or corrupted graphics)
byuu

Post by byuu »

The base unit has very primitive RTC functionality, and the most simplistic modem faking around. It's bad enough that I don't think it fools anything. Need more info to emulate that stuff further. Or a base unit to run my own tests on, which seems unlikely. I can't even find one for sale in Japan.

The cart's memory mapper is supposedly mostly correct, but possible has some small issues.

The flash cart commands are extremely primitive, and stuff like write enable is more pattern recognition than understanding what each write actually does.

A lot of BS-X stuff relies on the BIOS, and the only way to get that (properly) is to run through the actual BIOS and select the game from the loader menu. But since I don't fake the time / deleted flag / etc etc, you can't even start games that way very well without hacking the header.
tetsuo55
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Post by tetsuo55 »

byuu wrote:But since I don't fake the time / deleted flag / etc etc, you can't even start games that way very well without hacking the header.
This we can fix with the PCB/XML file can we not?

Set the game header to new/fresh, and add a note to the PCB file of which time to use
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Post by MatthewCallis »

Just an FYI, I've been dumping several BS-X memory packs with great success and have several fresh dumps on my site.

They aren't all emulated, and they don't all work in the same emulators, though SNESGT has the best success rate.

Any of the magazines have to have the base cart or there's no font data.

If anybody can use the raw cart dump, the full dump that's not yet split, shoot me an email and I can post them up. The whole point was to help progress the emulation of them and some have interesting bits of ascii in them, from driver names, dates and companies to just odd things.
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