Question Switches for Controller and AV out?

Papa J

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Hi all,

I was wondering if someone could tell me or point me towards somewhere that tells me how people wire up switches that change the controller and/or AV from internal to external ports? I've seen them on several portables and I've never seen an explanation of how they're done.

Thanks in advance for the help!
 

jefflongo

Broke BitBuilt
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For a controller port, you would just switch the data line. For example the player 1 data line from the Wii motherboard would be hooked up to the center pin on the switch, and the data line to the external port and the data line to your internal controller would be the things the switch could connect it to.

For AV, the concept is the same. The composite signal from the Wii goes to the center pin, and hook up the composite input to the screen as well as the composite pin on the AV port to switch between. Note that you don't need a switch for video, you can hook up both in parallel, however this will degrade the video quality on both devices, so I would recommend using a switch.

If you want to use a video signal that's not 1 wire (HDMI, vga, component) it's a little more complicated. You would probably want to use a digital switch IC that's capable of handling video signals. An elegant solution which I have recently used is to have vga go to the internal screen and composite go to the external AV port. Since these are independent, you can hook up both without any loss in video quality. However you would need to hook up a switch to connect mode to either 3.3v (for vga) or gnd (for composite).
 

Papa J

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so to clarify, for a VGA onboard/Composite out setup, I would just need to run the mode from the gpu to a switch on one side, continue the mode from the centre pin to the screen, and connect 3.3v to the third pin?
 
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