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View topic - Zoop: Is your "checksum" proprietary?

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Michael Montague
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Zoop: Is your "checksum" proprietary?
Post Posted: Mon Dec 20, 1999 7:17 am
Hey Zoop. Just wanted to innocently ask if your checksum code for carts was up for grabs. :)

You have invented the absolute perfect system for allowing an emulator to auto configure itself to the cart inserted.

I'm open to anything: A licensing fee, a callable .lib, or signing away my first born. :)

I will of course understand completely if this is out of the question. :) It is definatly one of MEKA's many many cool features.

- Mike
 
  • Joined: 24 Jun 1999
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Post Posted: Mon Dec 20, 1999 4:38 pm

Zoop's (c) (r) (tm) Proprietary (c) (r) (tm) Checksum (c) (r) (tm) <--- don't even dare stealing it!

Quote
> Hey Zoop. Just wanted to innocently ask if your checksum code for carts was up for grabs. :)
> You have invented the absolute perfect system for allowing an emulator to auto configure itself to the cart inserted.
> I'm open to anything: A licensing fee, a callable .lib, or signing away my first born. :)

Yeah, right.
Licensing fee cost a Meka registration, some chocolate and a christmas gift ^_^

Quote
> I will of course understand completely if this is out of the question. :) It is definatly one of MEKA's many many cool features.

Well, seriously, it isn't real hard to reproduce in your own emulator, you don't need to use the same exact calculation method.
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Michael Montague
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Post Posted: Tue Dec 21, 1999 11:05 am
Quote
>
> Zoop's (c) (r) (tm) Proprietary (c) (r) (tm) Checksum (c) (r) (tm) <--- don't even dare stealing it!

Run away! Run away! Before he taunts me a second time!

Quote
> Yeah, right.
> Licensing fee cost a Meka registration, some chocolate and a christmas gift ^_^

Doh! Too late!

Quote
> Well, seriously, it isn't real hard to reproduce in your own emulator, you don't need to use the same exact calculation method.

The main reason I asked is because I thought all of us emu developers could come up with a "standard" way of identifying a cart. Your checksum stuff is definatly a good idea.

Anyway, after seeing the way you figure out the cart name, special settings, and patches I realized that there wasn't an easier way. :)

I was also thinking about storing some extra information about the game. I guess the possibilities are limitless, but one could have a database of stuff that included Pro Action Replay codes, controls, or maybe even credit for the guy who dumped it.

Alternatively I wondered if anyone ever attempted to come up with a standard header or footer on carts? I figure if a few of the more popular emulators all supported the same format the rest of us would be very compelled to also. :)

So that's basically the reason for the inquiry. Any thoughts or comments?
 
JOSE MANUEL DELgado Mendi
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Post Posted: Tue Dec 21, 1999 9:54 pm
Hello :)

Yes. I interested in make a checksum for Calypso, or to make Calypso compatible with the meka.nam file. I working on put a checksum in Calypso. I have the ITU standard CRC32 Polinomial working, but your checksum is totally different!!!!. If you pusblish the code, i could make Calypso compatible with Meka. Well, we have to speak about the savegame file format aslo.

Saludos,

JMD

PD: Could you send me the SMS bios, or tell an URL. Thanks
 
Nyef
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Let's play "guess the chechsum procedure" ^_^
Post Posted: Wed Dec 22, 1999 1:54 pm
Quote
> I have the ITU standard CRC32 Polinomial working, but your checksum is totally different!!!!.

Have you tried treating the file as an array of 32-bit quantities and XORing them together? Adding them together? C'mon, play "guess the checksum procedure"! ^_^

Or you could try creating files with various sizes and contents and see what the checksums are and try to find a pattern.

Quote
> Well, we have to speak about the savegame file format aslo.

If you mean battery file, there is only one obvious format. If you mean save state file, then I'd be interested in hearing this too. ^_^

Quote
> PD: Could you send me the SMS bios, or tell an URL. Thanks

Ever get the feeling that this request will keep popping up, and nobody will believe that they don't really need it until they actually have it?

--Nyef
 
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Meka 2000 (developers, read!)
Post Posted: Wed Dec 22, 1999 5:59 pm
Quote
> Yes. I interested in make a checksum for Calypso, or to make Calypso compatible with the meka.nam file.

And what about the copyright on the MEKA.NAM file that take a lot of time to be maintened? ^_^
Hehe

Quote
>I working on put a checksum in Calypso. I have the ITU standard CRC32 Polinomial working, but your checksum is totally different!!!!. If you pusblish the code, i could make Calypso compatible with Meka. Well, we have to speak about the savegame file format aslo.

Alright. In all cases Meka is going to be rewritten from stratch, sooner or later.
It'll be interesting to work together on specifications for all aspects, like checksum and so.
The new Meka should be open source, and the first version released will be probably nothing but a Makefile.
So basically I would like it to be an open emulator in the sense that every developers could work on it if they want to.

Now I would like to know if anyone if interested in actually working on it.
Not just passively following the changes or pasting half of them in your own emulator ;-) but working on it, in the sense merging our forces.
All together, you know. Nothing is sure of defined right now, It still must be discussed. But that's an interesting idea.

Quote
> PD: Could you send me the SMS bios, or tell an URL. Thanks

What for?
(sorry, I had to. Nyef suggested it anyway :)
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Nyef
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Re: Meka 2000 (developers, read!)
Post Posted: Wed Dec 22, 1999 6:53 pm
Quote
> > Yes. I interested in make a checksum for Calypso, or to make Calypso compatible with the meka.nam file.

> And what about the copyright on the MEKA.NAM file that take a lot of time to be maintened? ^_^
> Hehe

I know I couldn't be bothered maintaining a database such as that. I'd much rather be coding. ^_^

Quote
> >I working on put a checksum in Calypso. I have the ITU standard CRC32 Polinomial working, but your checksum is totally different!!!!. If you pusblish the code, i could make Calypso compatible with Meka. Well, we have to speak about the savegame file format aslo.

> Alright. In all cases Meka is going to be rewritten from stratch, sooner or later.

Will the new version double as an email client? "All programs attempt to expand until they can read mail. Those that can't are replaced by those that can."

Quote
> It'll be interesting to work together on specifications for all aspects, like checksum and so.

This would be interesting and a good idea even if we don't join forces as suggested below.

Quote
> The new Meka should be open source, and the first version released will be probably nothing but a Makefile.

That's an awful small amount of code to start a project with. No CPU core? No renderer? No file loader?

Quote
> So basically I would like it to be an open emulator in the sense that every developers could work on it if they want to.

Like DarcNES, you mean? ^_^

Quote
> Now I would like to know if anyone if interested in actually working on it.
> Not just passively following the changes or pasting half of them in your own emulator ;-) but working on it, in the sense merging our forces.

I might be interested in this. Might.

Quote
> All together, you know. Nothing is sure of defined right now, It still must be discussed. But that's an interesting idea.

Yes, discussing things is an interesting idea. ^_^

Even if we don't join forces on one emulator, I wouldn't mind seeing some standards for file types...

Quote
> > PD: Could you send me the SMS bios, or tell an URL. Thanks

> What for?
> (sorry, I had to. Nyef suggested it anyway :)

Teehee. ^_^
 
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Re: Let's play "guess the chechsum procedure" ^_^.... OK
Post Posted: Thu Dec 23, 1999 3:48 am
Quote
> > I have the ITU standard CRC32 Polinomial working, but your checksum is totally different!!!!.

> Have you tried treating the file as an array of 32-bit quantities and XORing them together? Adding them together? C'mon, play "guess the checksum procedure"! ^_^

> Or you could try creating files with various sizes and contents and see what the checksums are and try to find a pattern.

n = filesize in bits
z = filesize zipped in bits
m = checksum

m = (n*z)/2
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Does this mean we'll finally see a Linux port of Meka?
Post Posted: Thu Dec 23, 1999 9:16 am
Quote
> > Yes. I interested in make a checksum for Calypso, or to make Calypso compatible with the meka.nam file.

> And what about the copyright on the MEKA.NAM file that take a lot of time to be maintened? ^_^
> Hehe

> >I working on put a checksum in Calypso. I have the ITU standard CRC32 Polinomial working, but your checksum is totally different!!!!. If you pusblish the code, i could make Calypso compatible with Meka. Well, we have to speak about the savegame file format aslo.

> Alright. In all cases Meka is going to be rewritten from stratch, sooner or later.
> It'll be interesting to work together on specifications for all aspects, like checksum and so.
> The new Meka should be open source, and the first version released will be probably nothing but a Makefile.
> So basically I would like it to be an open emulator in the sense that every developers could work on it if they want to.

> Now I would like to know if anyone if interested in actually working on it.
> Not just passively following the changes or pasting half of them in your own emulator ;-) but working on it, in the sense merging our forces.
> All together, you know. Nothing is sure of defined right now, It still must be discussed. But that's an interesting idea.

> > PD: Could you send me the SMS bios, or tell an URL. Thanks

> What for?
> (sorry, I had to. Nyef suggested it anyway :)
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Jose Manuel Delgado
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Re: Meka 2000 (developers, read!)
Post Posted: Thu Dec 23, 1999 4:41 pm
If you make Meka 2000 free source, I could contribute to the maintain of the program.

But I want anyway to work in my emulator. It is a small project, and there is another way of working togheter: publish the hacks or bugs that we could find. Example: I'm going to publish my VDP emulation code, so any finds a BUG i can solve them, and anybody can read it. The same with the Games Database and the checksum. You can decide one or another.

Saludos,

JMD
 
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Re: Meka 2000 (developers, read!)
Post Posted: Thu Dec 23, 1999 6:32 pm
Quote
> Alright. In all cases Meka is going to be rewritten from stratch, sooner or later.
> It'll be interesting to work together on specifications for all aspects, like checksum and so.
> The new Meka should be open source, and the first version released will be probably nothing but a Makefile.

Just a makefile? Wow, that's just barely enough to emulate My Hero.


Quote
> So basically I would like it to be an open emulator in the sense that every developers could work on it if they want to.

> Now I would like to know if anyone if interested in actually working on it.

Well count me in: although I probably wouldn't have much to contribute to the core emulation itself (I know more about SMS's than the average joe, but not enough to contribute something new), I might like to contribute some auxilliary features such as a more flexible debugger, charset editor... hey, maybe even a built in assembler! Or not!

Quote
> Not just passively following the changes or pasting half of them in your own emulator ;-) but working on it, in the sense merging our forces.

How about if I worked on a win32 port? If for no other reason than that I can't find a soundcard that will do 44.1khz sample rates under dos.

Quote
> All together, you know. Nothing is sure of defined right now, It still must be discussed. But that's an interesting idea.

One happy Meka Fam-i-ly.
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Re: Meka 2000 (developers, read!)
Post Posted: Thu Dec 23, 1999 8:46 pm
Quote
> > Alright. In all cases Meka is going to be rewritten from stratch, sooner or later.
> > It'll be interesting to work together on specifications for all aspects, like checksum and so.
> > The new Meka should be open source, and the first version released will be probably nothing but a Makefile.
> Just a makefile? Wow, that's just barely enough to emulate My Hero.

Geez. What I meant is that even very early stages of development will be made public.

Quote
> Well count me in: although I probably wouldn't have much to contribute to the core emulation itself (I know more about SMS's than the average joe, but not enough to contribute something new), I might like to contribute some auxilliary features such as a more flexible debugger, charset editor... hey, maybe even a built in assembler! Or not!

Oh yes! I'm posting the first specs I wrote in a minute, you'll have work to do ;)
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Re: Meka 2000 (developers, read!)
Post Posted: Fri Dec 24, 1999 10:36 am
Oc> And what about the copyright on the MEKA.NAM file that take a lot of time to be maintened? ^_^
> Hehe
Ny> I know I couldn't be bothered maintaining a database such as that. I'd much rather be coding. ^_^

With no offense, I think it is that kind of things that distinguish an average emulator and an awesome one.
You know, the little things here and here..

Oc> Alright. In all cases Meka is going to be rewritten from stratch, sooner or later.
Ny> Will the new version double as an email client? "All programs attempt to expand until they can read mail. Those that can't are replaced by those that can."

Bwahahaha ^_^
Seriously, I did plan a HTML viewer. Why not an e-mail client, so?

Oc> It'll be interesting to work together on specifications for all aspects, like checksum and so.
Ny> This would be interesting and a good idea even if we don't join forces as suggested below.

I'm going to revamp my savegame format for Meka. Will publish it's specifications when it's done.

Oc> The new Meka should be open source, and the first version released will be probably nothing but a Makefile.
Ny> That's an awful small amount of code to start a project with. No CPU core? No renderer? No file loader?

Nothing. Everything should be done together, I mean publicly. After discussing about the pros and cons of the different things.
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Nyef
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Re: Meka 2000 (developers, read!)
Post Posted: Fri Dec 24, 1999 4:59 pm
Quote
> Oc> And what about the copyright on the MEKA.NAM file that take a lot of time to be maintened? ^_^
> > Hehe
> Ny> I know I couldn't be bothered maintaining a database such as that. I'd much rather be coding. ^_^

> With no offense, I think it is that kind of things that distinguish an average emulator and an awesome one.
> You know, the little things here and here..

I know. But it still doesn't interest me. I prefer to work on emulating stuff instead adding user features.

On the other paw, if I think of a feature that I want to have, I'll add it. I'd add support for checksum databases, but I don't want to have to maintain the databases themselves.

Quote
> Oc> Alright. In all cases Meka is going to be rewritten from stratch, sooner or later.
> Ny> Will the new version double as an email client? "All programs attempt to expand until they can read mail. Those that can't are replaced by those that can."

> Bwahahaha ^_^
> Seriously, I did plan a HTML viewer. Why not an e-mail client, so?

The way I was going to add an email client to DarcNES was to emulate a computer that has an email client for it. ^_^

Quote
> Oc> It'll be interesting to work together on specifications for all aspects, like checksum and so.
> Ny> This would be interesting and a good idea even if we don't join forces as suggested below.

> I'm going to revamp my savegame format for Meka. Will publish it's specifications when it's done.

Oh, goody. Then we get to look it over and find all the bits you missed. ^_^

Quote
> Oc> The new Meka should be open source, and the first version released will be probably nothing but a Makefile.
> Ny> That's an awful small amount of code to start a project with. No CPU core? No renderer? No file loader?

> Nothing. Everything should be done together, I mean publicly. After discussing about the pros and cons of the different things.

Design by committee? Whatever happend to "Show us the code"?

Seriously, just throw togetjer a primitive SMS emulator and call that the first version. If people start working on it, it should improve in short order.

--Nyef
 
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Re: Meka 2000 (developers, read!)
Post Posted: Sun Dec 26, 1999 5:51 am
Quote
> > Oc> The new Meka should be open source, and the first version released will be probably nothing but a Makefile.
> > Ny> That's an awful small amount of code to start a project with. No CPU core? No renderer? No file loader?

> > Nothing. Everything should be done together, I mean publicly. After discussing about the pros and cons of the different things.

> Design by committee? Whatever happend to "Show us the code"?

> Seriously, just throw togetjer a primitive SMS emulator and call that the first version. If people start working on it, it should improve in short order.

> --Nyef

OK... so I'm not a developer, but I have to agree with that one.
I suggest that you just get a bare-bones no bells & whistles SMS emulator for the first release.
Just something that runs the game, nothing more. No save-state, no frameskipping, no auto-slowdown, nothing.
After that, everything else can be developed by collaboration, Everybody can submit what they would like included to a central "agency" (for lack of a better word) for 'approval' ("That looks good, we'll use it")
But then again, I'm not a programmer of any description...

~unfnknblvbl
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Re: Meka 2000 (developers, read!)
Post Posted: Sun Dec 26, 1999 10:17 pm
Problem is that everything will have to be thought in advance to follow the specs I gave.
I don't want it to be an "ordinary" emulator. I mean, you can write a (crap) SMS emulator in 500 lines of codes - excluding CPU emulation of course, but that's not the point.
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