Topic: GBA Tunnel?

[Pale]

Here is a theory I'm thinking I may explore a bit but I wanted to bounce it off you guys.

Multiplayer GBAing is something very similar to lan gaming.  Multiple systems, multiple games (usually), cable to send and receive vital information over.  Now, theoretically, if you could rip apart the cable and stick an rj45 plug on you should be able to receive some sort of signals into a computer.  Once those signals were decipherred (if possible) you could then use the hacked together cable to play over a home lan, then just use tunneling technology for online play.  It sounds kind of crazy but you may not even have to decipher the proper signals as long as each rj45 is stuck on in the same way.

Alright, I think i'm gonna go rip open a link cable...

[Grey Ninja]

I don't think it would be that easy, but if you get it working, let me know.  I have often wondered about that myself, but I have never really looked into the GBA networking protocols.

[Round Eye]

You may have better luck going through the parrellel port as it is easier to manipulate and program for.  With RS232 serial port the TX and RX lines need 13.5 volts to be able to work, I doubt that the GBA cable outputs that voltage level.  Most likely 3.5 or 5 volts.  In order to use the serial port you would need an external RS232 driver circuit<--not too hard to do, it consists of a single IC.  Just be carfull not to blow up your parrellel port, you may want to use some opti isolation.

[Bartman3010]

It would be somewhat possible, but the broadband/modem cable needs to think as a GBA link-up cable.  

[Pale]

The voltage is definately an issue.  I always overlook something in my scheming.    Serial would prolly be could, but I wonder if USB would be possible just to make it a little more modern.  I'm definately gonna grab a link up cable and at least see if I can pull it a part and analyze the different signals in a computer.  I'll keep you all posted.

edit: the only thing holding me back is the possibility of frying my gba by sending too much juice back at it or something.  Do you guys think that will be an issue?

[AngusPodgorny]

It would be tough.  I've experimented with connecting the Gamecube controller port to a Strongarm-based device (Cerfcube) via the Strongarm's GPIO pins.  I successfully read messages from the GCN, but the timing was really tricky.  I don't know if a standard serial or parallel port would be flexible enough for the task.

I thought that a better approach might be to get a Skillz Cube Connection USB and try to write your own driver for it to support GBA tunneling, but it's likely that the device is only capable of talking to a controller.

-Angus

[phreak97]

does the pc really need to know whats going on? or could you just make it send everything it gets off to another computer and everything it recieves down the link cable? btw.. the gba ext port runs an led fine with no resistor, i guess that would give you some hint of the power that goes through the cable.. also if any one makes it connect to the pc.. dont forget the gba can boot off the cable.. you can find the timing for something using an led, one of the pins has power at intervals and there is another which has power when the first doesnt.. this doesnt happen if the gba has already booted from somewhere.
i guess this could mean with the right programing etc and an emulator with a few changes you could play roms off your pc using your gba and the link. or (probably easyer) use the gba as a game controller (the same way the gcn gbaplayer does).