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Beginners > How to build own Multiboot cable?

#86087 - BongoBob - Sun Jun 04, 2006 10:45 am

Hello everyone.

I'm new to GBA hombrew development, and am working through some tutorials (that I got from this forum), and wanna test some of my stuff out on an actual GBA. I know about multiboot cables, but I don't have 20+ bucks to shell out for an MBV2. I have a spare GBA link cable and parallel port to hack together, and saw this so I know it's possible, but that's very vague on what to connect to where. I just need to know what wire/pin on the parallel cord goes to what wire/pin on the GBA link cable.

Any help is much appreciated, and I can get pictures if needed.

Thanks in advance.

#86098 - wintermute - Sun Jun 04, 2006 1:05 pm

Xboo Communicator has a schematic and slightly clearer instructions.

http://www.devkitpro.org/downloads.shtml

The one thing that doesn't seem to be particularly clear is that the pinouts for the GBA are shown looking into the port on the GBA. The arrangement is mirrored when looking at a link cable plug head on.

The best cables for doing this are actually GBC cables - a lot of the GBA cables I looked at had wires missing.
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#86142 - BongoBob - Sun Jun 04, 2006 8:14 pm

Thanks man. I'm gonn try to hack it together after I eat :)

EDIT: I just noticed a severe problem that I don't know why I didn't notice before, but anyhow, It appears that there's no ground wire. My guess is that the ground connection at the end of the plug simply leads to the metal shielding around the connection, because I only have 4 wires on here, and I have all the connections on the plug.

If this is the case, what do I do to the gnd wire of the parallel port?

EDIT 2: I'm having the damndest time tryin to get past the rubber to see what color wires correspond to what pins on the parallel port. Is there a standard for the color of the wires?

#86331 - wintermute - Tue Jun 06, 2006 12:48 pm

You absolutely sure it's the ground wire that's missing? Such a cable probably wouldn't be very reliable for multiplayer.

Something I found with GBA multiplayer cables is that some only contain the connections for normal mode comms. In these cables SI is grounded on the master side, the 4 wires are usually SO -> SI, SD <-> SD, GND - GND & SC -> SC. Unfortunately you can't make an xboo cable with one :/

Trying to make cables isn't terribly easy without a continuity tester. Ideally you should have a multimeter but in a pinch you can use a couple of wires with a battery & a torch bulb or a buzzer.
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