How xband works....

Former Xbanders on SNES or Genesis can get in touch with each other here. Also for people who wish to help with the Xband revival project.
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rush6432
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How xband works....

Post by rush6432 »

Ok.... so for those that dont know how it works and thats probably all of you. The system is VERY similar to what back in the day was called a BBS... your modem would call the main server (Not the internet.....) and connect and check for mail (if you selected to check for mail) or to find an opponent. basically what it did was dump your name, the game you wanted to play, your phone number your dialing from to the server and search for another player that had dialed in looking for the same thing within a certain time frame. if it found a player, it would grab the players phone number and it would check the xbands on board ram to see if you had the game patch for the game you were wanting to play. if not, it would download this small very tiny patch and then disconnect. it would then dial the opponents number directly and you would be on your way to playing...
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If you didn't find anyone to play, it would tell you that it couldn't find an opponent and would check for the patch in ram on the modem, then set a flag inside stating that once you disconnected from xband, to put the modem into waiting mode and wait for a call to come in from an opponent.

This is just the basics of how it worked. any time you connected to find an opponent it would download the patch for the game if you didn't have it in saved ram already.

As for the actual functionality of how it worked, think of the xband modem as a modem and a game genie in one more or less. it would insert its OWN code (game patches) between the game cartridge and the genesis and also could snag the controller inputs and send that data out on the phone line. it also grabbed a bunch of other important stuff but thats all technical mumbo jumbo thats not worth mentioning now.


Anyway, just thought id explain to all you new guys out there or people that were wondering how it worked.
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Post by Isaac [GER] »

Wow, thanks for the exact explanation :D
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Auto-Fox
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Post by Auto-Fox »

Huh, elegantly simple... too bad there was so much proprietary stuff involved, which I understand is a big hindrance to reviving the service.
It's too bad the modems didn't provide a "true" direct-dial service, like the NetLink. I heard that some prototype versions of the system read the game patches off data cards, rather than downloading, though I can see why they picked the latter system in the end.
Still, data cards would have made things a whole lot simpler on us now, wouldn't they...
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Post by Warp2063 »

Auto-Fox wrote:Still, data cards would have made things a whole lot simpler on us now, wouldn't they...
Except for the fact that it's more hardware to produce, meaning more cost. The cards and the reader just add more things that could go wrong, too. Also, it's one more thing that the user could lose. Finally, if Catapult needed to update a patch, a data card would become outdated and useless. By downloading the patches, Catapult could check to make sure that everyone is using the latest version for stability and anti-cheating purposes.
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Post by Auto-Fox »

Ruin my rose-tinted views, why don't you. I'm just thinking that the cards would have made it easier to track down the patches than having to rip them off old XBAND hardware.
But, of course, I doubt the developers ever considered a situation like the one we're facing currently. And for the people playing it, the download system was certainly the most convenient way to play.
Just sayin', it would be handy if we could potentially get our hands on physical copies of the patches, but alas, we can't.
Didn't the production XBAND modems have a little slot for Phone Cards or something, though?
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Post by Warp2063 »

Yeah, you could either pay for connects with a credit card, or you could buy pre-paid cards that would give you a certain number of "Connects". Each time you connected to the XBAND server to download XMAIL or request a match, it would charge you one "Connect."

Sorry for spoiling your view. It would be useful to have physical copies of the patches. Just a weird way for a company to do things.
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Post by Auto-Fox »

Huh, I wonder how collectible those pre-paid cards would be today...
Anyway, no problem, and yeah, it would be. Just wishful thinking on my part, nothing more.
Hmm. Y'know, I wonder if some kind of phone-box hack could fool and XBAND modem into thinking it had found another player... just idle speculation...
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Post by Warp2063 »

The XBAND doesn't find another player. The XBAND server would. As was said before, you'd dial the XBAND server. If the server didn't find someone for you to play with, it would instruct your modem to wait for an incoming call. If it did find another player, it would instruct your modem to dial that other player, whose modem would have previously been instructed to wait.

To connect two XBANDs today, we would either have to modify both XBANDs so that we can manually instruct them to wait or to dial (like we can with the NetLink), or we would have to recreate the XBAND server. Either method is quite difficult, and both have their downsides.
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Post by Auto-Fox »

I know that. But, unless I'm mistaken, the actual PLAY is direct-dial between two XBAND modems, correct?
Once again, I must say that everything I'm saying here is purely speculative. I'm no communications technology expert.
But, anyway, couldn't a device be constructed that, when you got your XBAND to dial out to try and find the server, would automatically bounce back the "searching" and then "found player" signals?
Conceivably, two such devices hooked to two XBANDs could facilitate play between two XBAND modems, either in the same room or at separate locations over a standard analog phone-line.
Of course, the problem would be that probably the only game you'd be able to get to work reliably would be Weapon Lord.
Not to mention you'd have to build your own equipment.
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Post by Warp2063 »

What you're suggesting is to build a custom modem. From scratch.

A modem is a device that MODulates, or converts, a digital signal into some other form. In this case, the digital data is converted into very complex sounds. These sounds are conveyed over a telephone line, where another modem DEModulates the audio back into digital data. This is where you get "modem" from.

Since a we need a modem to demodulate the XBAND's signal anyway, it would be far easier to use a computer to control the modem (just like the original XBAND server) than it would be to build a custom device to control a modem.
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Post by Warp2063 »

Long story short - connecting to an XBAND modem is easy. Talking to it is the hard part, as we don't know what exactly it says, and what responses it's expecting. If we had both the client and the server code, it would be relatively simple to write a program to send and receive the correct responses. However, we don't. Which means a lot of reverse-engineering and guesswork, which takes a lot of time and effort. We're trying to get the code, but not many people have it, and the people who have it aren't necessarily willing to part with it.
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Post by Xband411 »

Here's information that a former employee named Larry posted online:
The big sticking point is the XBand modem connectivity. XBand used an ANI phone bank to handle incoming calls; these are still quite expensive, both in setup and in monthly running costs. Perhaps you could change this to a more distributed service, having the XBand modem dial a local dial-in modem on someone's Linux box, then spoofing the network traffic (apparently a modified form of ADSP (Appletalk)) over the net to a "central" XBand server. But that would be an astonishing amount of work.
Here's a link to the thread on another forum if you'd care to read more of his responses:

http://www.stageselect.com/forum/Legacy ... px?TID=542
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Post by Undertaker_COTN »

Warp2063 wrote:We're trying to get the code, but not many people have it, and the people who have it aren't necessarily willing to part with it.
What will make them willing to part with it??
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rush6432
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Post by rush6432 »

I honestly dont know. money would probably do it but how much im not really sure.
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Post by segasaturndude »

for all we know it could cost thousands if not millions to buy things like this. we need to be careful
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